User manual D-LINK DGS-3024

D-Link TM DGS-3024 Managed 24-Port Gigabit Ethernet Switch Manual DGS-3024 Gigabit Ethernet Switch Manual Information in this document is subject to change without notice. © 2004 D-Link Computer Corporation. All rights reserved. Reproduction in any manner whatsoever without the written permission of D-Link Computer Corporation is strictly forbidden. Trademarks used in this text: D-Link and the D-Link logo are trademarks of D-Link Computer Corporation; Microsoft and Windows are registered trademarks of Microsoft Corporation. Other trademarks and trade names may be used in this document to refer to either the entities claiming the marks and names or their products. D-Link Computer Corporation disclaims any proprietary interest in trademarks and trade names other than its own. FCC Warning This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with this manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense. CE Mark Warning This is a Class A product. In a domestic environment, this product may cause radio interference in which case the user may be required to take adequate measures. Warnung! Dies ist ein Produkt der Klasse A. Im Wohnbereich kann dieses Produkt Funkstoerungen verursachen. In diesem Fall kann vom Benutzer verlangt werden, angemessene Massnahmen zu ergreifen. Precaución! Este es un producto de Clase A. En un entorno doméstico, puede causar interferencias de radio, en cuyo case, puede requerirse al usuario para que adopte las medidas adecuadas. Attention! Ceci est un produit de classe A. Dans un environnement domestique, ce produit pourrait causer des interférences radio, auquel cas l`utilisateur devrait prendre les mesures adéquates. Attenzione! Il presente prodotto appartiene alla classe A. Se utilizzato in ambiente domestico il prodotto può causare interferenze radio, nel cui caso è possibile che l`utente debba assumere provvedimenti adeguati. VCCI Warning December 2004 P/N 6DGS3024..01 ii DGS-3024 Gigabit Ethernet Switch Manual Table of Contents Preface ............................................................................................................................................................................... viii Intended Readers............................................................................................................................................................ viii Notes, Notices, and Cautions ......................................................................................................................................... viii Safety Instructions..................................................................................................................................................................x Introduction............................................................................................................................................................................. 1 Features ................................................................................................................................................................................ 1 Ports .................................................................................................................................................................................. 1 Performance Features........................................................................................................................................................ 1 Management...................................................................................................................................................................... 1 Unpacking and Setup.............................................................................................................................................................. 3 Unpacking ............................................................................................................................................................................. 3 Installation ............................................................................................................................................................................ 3 Desktop or Shelf Installation............................................................................................................................................. 4 Rack Installation ............................................................................................................................................................... 4 Power on ............................................................................................................................................................................... 5 Power Failure .................................................................................................................................................................... 5 External Redundant Power System ....................................................................................................................................... 5 Identifying External Components ......................................................................................................................................... 7 Front Panel ........................................................................................................................................................................... 7 Rear Panel ............................................................................................................................................................................ 7 Side Panels............................................................................................................................................................................ 7 LED Indicators...................................................................................................................................................................... 8 Connecting the Switch ............................................................................................................................................................ 9 Switch to End Node............................................................................................................................................................... 9 Switch to Hub or Switch...................................................................................................................................................... 10 Switch to Core Router Switch ............................................................................................................................................. 10 Web-Based Network Management...................................................................................................................................... 12 Introduction........................................................................................................................................................................... 12 Login to Web Manager......................................................................................................................................................... 12 Web-based User Interface................................................................................................................................................... 13 Areas of the User Interface ................................................................................................................................................. 13 Configuration ........................................................................................................................................................................ 15 IP Address ............................................................................................................................................................................. 15 iii DGS-3024 Gigabit Ethernet Switch Manual Switch Information ............................................................................................................................................................... 16 Advanced Settings................................................................................................................................................................. 17 Port Configuration................................................................................................................................................................ 19 Port Mirroring ...................................................................................................................................................................... 20 IGMP...................................................................................................................................................................................... 21 IGMP Snooping .................................................................................................................................................................. 21 Static Router Ports Entry .................................................................................................................................................... 22 Spanning Tree ....................................................................................................................................................................... 23 802.1w Rapid Spanning Tree.......................................................................................................................................... 23 Port Transition States ...................................................................................................................................................... 23 Edge Port......................................................................................................................................................................... 24 P2P Port .......................................................................................................................................................................... 24 802.1d/802.1w Compatibility ......................................................................................................................................... 24 STP Switch Settings............................................................................................................................................................. 25 STP Port Settings ................................................................................................................................................................ 27 Forwarding ............................................................................................................................................................................ 28 Unicast Forwarding............................................................................................................................................................ 28 Multicast Forwarding ......................................................................................................................................................... 29 VLANs.................................................................................................................................................................................... 30 Understanding IEEE 802.1p Priority .............................................................................................................................. 30 VLAN Description.......................................................................................................................................................... 30 Notes About VLANs on the DGS-3024 ......................................................................................................................... 31 IEEE 802.1Q VLANs ..................................................................................................................................................... 31 802.1Q VLAN Tags........................................................................................................................................................ 32 Port VLAN ID................................................................................................................................................................. 33 Tagging and Untagging................................................................................................................................................... 34 Ingress Filtering .............................................................................................................................................................. 34 Default VLANs ............................................................................................................................................................... 35 VLAN and Trunk Groups ............................................................................................................................................... 35 Static VLAN Entry............................................................................................................................................................... 35 GVRP Settings..................................................................................................................................................................... 37 SNTP Setting ......................................................................................................................................................................... 39 Time Setting ........................................................................................................................................................................ 39 Time Zone and DST ............................................................................................................................................................ 41 QoS ......................................................................................................................................................................................... 43 Advantages of QoS ......................................................................................................................................................... 43 Understanding QoS......................................................................................................................................................... 43 Traffic Control .................................................................................................................................................................... 45 iv DGS-3024 Gigabit Ethernet Switch Manual 802.1p Default Priority ....................................................................................................................................................... 46 802.1p User Priority ........................................................................................................................................................... 47 QoS Scheduling Mechanism ............................................................................................................................................... 47 Link Aggregation .................................................................................................................................................................. 48 MAC Notification.................................................................................................................................................................. 50 Global Settings.................................................................................................................................................................... 50 Port Settings........................................................................................................................................................................ 51 System Log Server ................................................................................................................................................................ 53 Port Access Entity ................................................................................................................................................................. 55 802.1x Port-Based Access Control ................................................................................................................................. 55 Authentication Server ..................................................................................................................................................... 55 Authenticator................................................................................................................................................................... 56 Client............................................................................................................................................................................... 57 Authentication Process.................................................................................................................................................... 57 Port-Based Network Access Control .............................................................................................................................. 57 Configure Authenticator ..................................................................................................................................................... 58 Local users .......................................................................................................................................................................... 61 802.1x Capability Settings .................................................................................................................................................. 61 Initialize Port(s)............................................................................................................................................................... 63 Reauthenticate Port(s) ..................................................................................................................................................... 64 RADIUS Server ................................................................................................................................................................... 65 Static ARP Settings ............................................................................................................................................................... 66 Management .......................................................................................................................................................................... 67 Security IP ............................................................................................................................................................................. 67 User Accounts........................................................................................................................................................................ 67 Admin and User Privileges ............................................................................................................................................. 69 SNMP V3 ............................................................................................................................................................................... 69 SNMP User Table ............................................................................................................................................................... 70 SNMP View Table ............................................................................................................................................................... 71 SNMP Group Table............................................................................................................................................................. 73 SNMP Community Table Configuration ............................................................................................................................. 75 SNMP Host Table ............................................................................................................................................................... 76 SNMP Engine ID................................................................................................................................................................. 77 SNMP Trap ......................................................................................................................................................................... 77 Monitoring ............................................................................................................................................................................. 78 v DGS-3024 Gigabit Ethernet Switch Manual Port Utilization ...................................................................................................................................................................... 78 Packets ................................................................................................................................................................................... 79 Received (RX)...................................................................................................................................................................... 79 UMB Cast (RX) ................................................................................................................................................................... 81 Transmitted (TX)................................................................................................................................................................. 84 Errors ..................................................................................................................................................................................... 85 Received (RX)...................................................................................................................................................................... 86 Transmitted (TX)................................................................................................................................................................. 88 Size.......................................................................................................................................................................................... 90 MAC Address ........................................................................................................................................................................ 92 Switch History Log ............................................................................................................................................................... 94 Browse ARP Table ................................................................................................................................................................ 96 IGMP Snooping Group ........................................................................................................................................................ 97 IGMP Snooping Forwarding ............................................................................................................................................... 97 VLAN Status ......................................................................................................................................................................... 98 Browse Router Port .............................................................................................................................................................. 98 Session Table ......................................................................................................................................................................... 99 Port Access Control ............................................................................................................................................................ 100 RADIUS Authentication .................................................................................................................................................... 100 Maintenance ........................................................................................................................................................................ 101 TFTP Services ..................................................................................................................................................................... 101 Download Firmware From TFTP Server ......................................................................................................................... 101 Download Settings from TFTP Server .............................................................................................................................. 101 Upload Settings to TFTP Server ....................................................................................................................................... 102 Upload Log to TFTP Server ............................................................................................................................................. 102 Ping Test .............................................................................................................................................................................. 102 Save Changes....................................................................................................................................................................... 103 vi DGS-3024 Gigabit Ethernet Switch Manual Reboot Services ................................................................................................................................................................... 104 Reboot ............................................................................................................................................................................... 104 Reset.................................................................................................................................................................................. 104 Reset System...................................................................................................................................................................... 105 Reset Config ...................................................................................................................................................................... 105 Logout .................................................................................................................................................................................. 105 Technical Specifications ..................................................................................................................................................... 107 Cable Lengths...................................................................................................................................................................... 109 Glossary ............................................................................................................................................................................... 110 Warranty and Registration Information .......................................................................................................................... 113 vii DGS-3024 Gigabit Ethernet Switch Manual Preface The DGS-3024 Manual is divided into chapters that describe the system installation and operating instructions with examples. Section 1, "Introduction" ­ Describes the Switch and its features. Section 2, "Installation" ­ Helps you get started with the basic installation of the Switch and also describes the front panel, rear panel, side panels, and LED indicators of the Switch. Section 3, "Connecting the Switch" ­ Tells how you can connect the Switch to your Ethernet/Fast Ethernet network. Section 4, "Introduction to Switch Management" ­ Introduces basic Switch management features, including password protection, SNMP settings, IP address assignment, and connecting devices to the Switch. Section 5, "Introduction to Web-based Switch Management" ­ Talks about connecting to and using the Web-based switch management feature on the Switch. Section 6, "Configuration" ­ A detailed discussion about configuring some of the basic functions of the Switch, including accessing the Switch information, using the Switch's utilities and setting up network configurations, such as Quality of Service, Port Mirroring, and configuring the Spanning Tree. Section 7, "Management" ­ A discussion of the security features of the Switch, including Security IP, User Accounts, and SNMP. Section 8, "Monitoring" ­ Features graphs and windows used in monitoring features and packets on the Switch. Section 9, "Maintenance" ­ Features information on Switch utility functions, including TFTP Services, Ping History, Save Changes, Switch History, and Reboot Services. Appendix A, "Technical Specifications" ­ The technical specifications of the DGS-3204. Appendix B, "Cable Lengths" ­ Information on cable types and maximum distances. Appendix C, "Glossary" ­ Lists definitions for terms and acronyms used in this document. Intended Readers The DGS-3024 Manual contains information for setup and management and of the DGS-3024 switch. This guide is intended for network managers familiar with network management concepts and terminology. Notes, Notices, and Cautions NOTE: A NOTE indicates important information that helps you make better use of your device. NOTICE: A NOTICE indicates either potential damage to hardware or loss of data and tells you how to avoid the problem. viii DGS-3024 Gigabit Ethernet Switch Manual CAUTION: A CAUTION indicates a potential for property damage, personal injury, or death. ix DGS-3024 Gigabit Ethernet Switch Manual Safety Instructions Use the following safety guidelines to ensure your own personal safety and to help protect your system from potential damage. Throughout this safety section, the caution icon ( ) is used to indicate cautions and precautions that you need to review and follow. Safety Cautions To reduce the risk of bodily injury, electrical shock, fire, and damage to the equipment, observe the following precautions. Observe and follow service markings. Do not service any product except as explained in your system documentation. Opening or removing covers that are marked with the triangular symbol with a lightning bolt may expose you to electrical shock. Only a trained service technician should service components inside these compartments. If any of the following conditions occur, unplug the product from the electrical outlet and replace the part or contact your trained service provider: ­ The power cable, extension cable, or plug is damaged. ­ An object has fallen into the product. ­ The product has been exposed to water. ­ The product has been dropped or damaged. ­ The product does not operate correctly when you follow the operating instructions. · · · · · · · Keep your system away from radiators and heat sources. Also, do not block cooling vents. Do not spill food or liquids on your system components, and never operate the product in a wet environment. If the system gets wet, see the appropriate section in your troubleshooting guide or contact your trained service provider. Do not push any objects into the openings of your system. Doing so can cause fire or electric shock by shorting out interior components. Use the product only with approved equipment. Allow the product to cool before removing covers or touching internal components. Operate the product only from the type of external power source indicated on the electrical ratings label. If you are not sure of the type of power source required, consult your service provider or local power company. To help avoid damaging your system, be sure the voltage selection switch (if provided) on the power supply is set to match the power available at your location: ­ 115 volts (V)/60 hertz (Hz) in most of North and South America and some Far Eastern countries such as South Korea and Taiwan ­ 100 V/50 Hz in eastern Japan and 100 V/60 Hz in western Japan ­ 230 V/50 Hz in most of Europe, the Middle East, and the Far East · · Also be sure that attached devices are electrically rated to operate with the power available in your location. Use only approved power cable(s). If you have not been provided with a power cable for your system or for any AC-powered option intended for your system, purchase a power cable that is approved for use in your country. The power cable must be rated for the product and for the voltage and current marked on the product's electrical ratings label. The voltage and current rating of the cable should be greater than the ratings marked on the product. x DGS-3024 Gigabit Ethernet Switch Manual Safety Instructions (continued) · To help prevent electric shock, plug the system and peripheral power cables into properly grounded electrical outlets. These cables are equipped with three-prong plugs to help ensure proper grounding. Do not use adapter plugs or remove the grounding prong from a cable. If you must use an extension cable, use a 3-wire cable with properly grounded plugs. Observe extension cable and power strip ratings. Make sure that the total ampere rating of all products plugged into the extension cable or power strip does not exceed 80 percent of the ampere ratings limit for the extension cable or power strip. To help protect your system from sudden, transient increases and decreases in electrical power, use a surge suppressor, line conditioner, or uninterruptible power supply (UPS). Position system cables and power cables carefully; route cables so that they cannot be stepped on or tripped over. Be sure that nothing rests on any cables. Do not modify power cables or plugs. Consult a licensed electrician or your power company for site modifications. Always follow your local/national wiring rules. When connecting or disconnecting power to hot-pluggable power supplies, if offered with your system, observe the following guidelines: ­ Install the power supply before connecting the power cable to the power supply. ­ Unplug the power cable before removing the power supply. ­ If the system has multiple sources of power, disconnect power from the system by unplugging all power cables from the power supplies. · Move products with care; ensure that all casters and/or stabilizers are firmly connected to the system. Avoid sudden stops and uneven surfaces. · · · · · General Precautions for Rack-Mountable Products Observe the following precautions for rack stability and safety. Also refer to the rack installation documentation accompanying the system and the rack for specific caution statements and procedures. Systems are considered to be components in a rack. Thus, "component" refers to any system as well as to various peripherals or supporting hardware. CAUTION: Installing systems in a rack without the front and side stabilizers installed could cause the rack to tip over, potentially resulting in bodily injury under certain circumstances. Therefore, always install the stabilizers before installing components in the rack. After installing system/components in a rack, never pull more than one component out of the rack on its slide assemblies at one time. The weight of more than one extended component could cause the rack to tip over and may result in serious injury. · Before working on the rack, make sure that the stabilizers are secured to the rack, extended to the floor, and that the full weight of the rack rests on the floor. Install front and side stabilizers on a single rack or front stabilizers for joined multiple racks before working on the rack. xi DGS-3024 Gigabit Ethernet Switch Manual Safety Instructions (continued) Always load the rack from the bottom up, and load the heaviest item in the rack first. Make sure that the rack is level and stable before extending a component from the rack. Use caution when pressing the component rail release latches and sliding a component into or out of a rack; the slide rails can pinch your fingers. After a component is inserted into the rack, carefully extend the rail into a locking position, and then slide the component into the rack. Do not overload the AC supply branch circuit that provides power to the rack. The total rack load should not exceed 80 percent of the branch circuit rating. Ensure that proper airflow is provided to components in the rack. Do not step on or stand on any component when servicing other components in a rack. NOTE: A qualified electrician must perform all connections to DC power and to safety grounds. All electrical wiring must comply with applicable local or national codes and practices. CAUTION: Never defeat the ground conductor or operate the equipment in the absence of a suitably installed ground conductor. Contact the appropriate electrical inspection authority or an electrician if you are uncertain that suitable grounding is available. CAUTION: The system chassis must be positively grounded to the rack cabinet frame. Do not attempt to connect power to the system until grounding cables are connected. Completed power and safety ground wiring must be inspected by a qualified electrical inspector. An energy hazard will exist if the safety ground cable is omitted or disconnected. xii DGS-3024 Gigabit Ethernet Switch Manual Protecting Against Electrostatic Discharge Static electricity can harm delicate components inside your system. To prevent static damage, discharge static electricity from your body before you touch any of the electronic components, such as the microprocessor. You can do so by periodically touching an unpainted metal surface on the chassis. You can also take the following steps to prevent damage from electrostatic discharge (ESD): 1. When unpacking a static-sensitive component from its shipping carton, do not remove the component from the antistatic packing material until you are ready to install the component in your system. Just before unwrapping the antistatic packaging, be sure to discharge static electricity from your body. When transporting a sensitive component, first place it in an antistatic container or packaging. Handle all sensitive components in a static-safe area. If possible, use antistatic floor pads and workbench pads and an antistatic grounding strap. 2. 3. Battery Handling Reminder CAUTION: Danger of explosion if battery is incorrectly replaced. Replace only with the same or equivalent type recommended by the manufacturer. Discard used batteries according to the manufacturer's instructions. xiii DGS-3024 Gigabit Ethernet Switch Manual 1 Introduction This section describes the features of the DGS-3024. Features The DGS-3024 was designed for departmental and enterprise connections. As an all-gigabit-port switch, it is ideal for backbone and server connection. Powerful and versatile, the switch eliminates network bottlenecks while giving users the capability to fine-tune performance Switch features include: Ports · · · Twenty-four high performance 1000BASE-T ports for making 10/100/1000 connections to a backbone, end stations, and servers. Four mini-GBIC (SFP) combo ports to connect fiber optic media to another switch, server or network backbone. RS-232 DCE Diagnostic port (console port) for setting up and managing the Switch via a connection to a console terminal or PC using a terminal emulation program. Performance Features · · · · · · · · · · · · · Store-and-forward switching scheme. Switching fabric: 48Gbps Max. Forwarding Rate: 35.7 million packets per second High-speed data forwarding rate of 1,488,095 pps per port at 100% of wire-speed for 1000 Mbps speed. Supports 8K MAC address. Supports four priority queues per port. Supports 512Kbytes buffer memory per switch. 802.1D Spanning Tree support. Can be disabled on the entire switch or on a per-port basis. 802.1Q Tagged VLAN support, including GVRP (GARP VLAN Registration Protocol). Support for up to 255 VLANs. IGMP snooping support per switch. Link aggregation support for up to four trunk groups and eight trunk members per group. Port-based 802.1x port access control. Management · · · · RS-232 console port for out-of-band network management via a console terminal. Spanning Tree Algorithm Protocol for creation of alternative backup paths and prevention of network loops. SNMP V.1, V2c1, and V3 network management, four groups of RMON. Flash memory for software upgrades. This can be done in-band via TFTP or out-of-band via the console. 1 DGS-3024 Gigabit Ethernet Switch Manual · Built-in SNMP management: Bridge MIB (RFC 1493) MIB-II (RFC 1213) 802.1P/Q MIB (RFC 2674) Ethernet-like MIB (RFC 1643) Private MIB Mini-RMON MIB (RFC 1757) ­ four groups. The RMON specification defines the counters for the receive functions only. However, the DGS-3024 provides counters for both receive and transmit functions. · · · · · · · · · · · · Supports Web-based management. TFTP Client support. BOOTP Client support. DHCP Client support. Password enabled. Telnet remote control console. Broadcast storm control. Multicast storm control. Command Line Interface support. Syslog support. SNTP support. SNMP Trap on MAC Notification support. 2 DGS-3024 Gigabit Ethernet Switch Manual 2 Unpacking and Setup This chapter provides unpacking and setup information for the switch. Unpacking Open the shipping carton of the switch and carefully unpack its contents. The carton should contain the following items: · · · · · · · A DGS-3024 24-Port Gigabit Layer 2 Ethernet switch A mounting kit: 2 mounting brackets and screws Four rubber feet with adhesive backing One or two AC power cords A printed QIG D-View 5.1 demo CD-ROM This Manual with Registration Card on CD-ROM If any item is found missing or damaged, please contact your local D-Link reseller for replacement. Installation Use the following guidelines when choosing a place to install the switch: · · · · The surface must support at least 4 kg. The power outlet should be within 1.82 meters (6 feet) of the device. Visually inspect the power cord and see that it is secured to the AC power connector. Make sure that there is proper heat dissipation from and adequate ventilation around the switch. Do not place heavy objects on the switch. 3 DGS-3024 Gigabit Ethernet Switch Manual Desktop or Shelf Installation When installing the switch on a desktop or shelf, the rubber feet included with the device should first be attached. Attach these cushioning feet on the bottom at each corner of the device. Allow adequate space for ventilation between the device and the objects around it. Figure 2-1. Installing rubber feet for desktop installation Rack Installation The DGS-3024 can be mounted in an EIA standard-sized, 19-inch rack, which can be placed in a wiring closet with other equipment. To install, attach the mounting brackets on the switch's side panels (one on each side) and secure them with the screws provided. Figure 2- 2A. Attaching the mounting brackets Then, use the screws provided with the equipment rack to mount the witch on the rack. 4 DGS-3024 Gigabit Ethernet Switch Manual Figure 2- 2B. Installing in an equipment rack Power on The switch can be used with AC power supply 100-240 VAC, 50 - 60 Hz. The switch's power supply will adjust to the local power source automatically and may be powered on without having any or all LAN segment cables connected. After the switch is plugged in, the LED indicators should respond as follows: · · All LED indicators except console will momentarily blink. This blinking of the LEDs indicates a reset of the system. The console LED indicator will blink while the switch loads onboard software and performs a self-test. When the POST is passed, the LED will become dark. If the POST fails, the indicator will light solid amber. This indicator lights solid green when the switch is being logged-in via out-of-band/local console management through the RS-232 console port using a straight-through serial cable. Power Failure As a precaution in the event of a power failure, unplug the switch. When power is resumed, plug the switch back in. External Redundant Power System The switch supports an external redundant power system. 5 DGS-3024 Gigabit Ethernet Switch Manual Figure 2-3. DPS-300 in DPS-900 case with DGS-3024 Figure 2-4. DPS-300 in DPS-800 case with DGS-3024 NOTE: See the DPS-300 documentation for more information. CAUTION: Do not use the Switch with any redundant power system other than the DPS-300. 6 DGS-3024 Gigabit Ethernet Switch Manual 3 Identifying External Components This chapter describes the front panel, rear panel, side panels, and LED indicators of the DGS-3024. Front Panel The front panel of the switch consists of LED indicators, an RS-232 communication port, 24 1000BASE-T ports, and four mini-GBIC combo ports. Figure 3-1. Front panel view · · · · An RS-232 DCE console port for setting up and managing the switch via a connection to a console terminal or PC using a terminal emulation program. Comprehensive LED indicators display the status of the switch and the network (see the LED Indicators section below). Twenty-four 1000BASE-T Ethernet ports for 10/100/1000 connections to a backbone, end stations, and servers. Four mini-GBIC combo ports to connect fiber optic media to another switch, server, core router switch, or network backbone. Rear Panel The rear panel of the switch contains an external Redundant Power Supply connector and an AC power connector. Figure 3-2. Rear panel view · The external Redundant Power Supply connector is used to connect the DGS-3024 to a DPS-300. An auto-switch circuit automatically switches to an external RPS once the internal power supply fails. Transition from internal to external supply shall not disturb normal operation. The AC power connector is a standard three-pronged connector that supports the power cord. Plug-in the female connector of the provided power cord into this socket, and the male side of the cord into a power outlet. Supported input voltages range from 100 ~ 240 VAC at 50 ~ 60 Hz. · Side Panels The right side panel of the switch contains two system fans (see the top part of the diagram below). The left side panel contains heat vents. 7 DGS-3024 Gigabit Ethernet Switch Manual Figure 3-3. Side panel views of the Switch · The system fans are used to dissipate heat. The sides of the system also provide heat vents to serve the same purpose. Do not block these openings, and leave at least 6 inches of space at the rear and sides of the switch for proper ventilation. Be reminded that without proper heat dissipation and air circulation, system components might overheat, which could lead to system failure. LED Indicators The LED indicators of the switch include Power, Console, RPS, Speed, and Link/Activity. The following shows the LED indicators for the switch along with an explanation of each indicator. Figure 3-4. LED indicators · · · · · Power ­ This indicator on the front panel lights solid green when the system is powered up and remains dark when the system is not powered on. RPS ­ This indicator is lit solid amber when the external Redundant Power Supply is in operation and remains dark when it is not in use or the main power is working normally. Console ­ This indicator blinks green when the system is booting up. It remains solid green when the system is operating properly. The LED is solid amber when the POST fails. Speed ­ This row of indicators will light solid green when the connection speed is operating at 1000 Mbps. An unlit LED indicates a connection speed of either 10 or 100 Mbps. Link/Act ­ This row of indicators for the 24 copper ports light solid green when there is a secure connection (or link) to a device on any of the ports. The LEDs blink green whenever there is reception or transmission (i.e. Activity--Act) of data occurring on a port. 8 DGS-3024 Gigabit Ethernet Switch Manual 4 Connecting the Switch This chapter describes how to connect the DGS-3024 to your Gigabit Ethernet network. Switch to End Node End nodes include PCs outfitted with a 10, 100, or 1000 Mbps RJ-45 Ethernet/Fast Ethernet/Gigabit Ethernet Network Interface Card (NIC) and most routers. An end node can be connected to the switch via a Category 3, 4, 5, or 5e UTP/STP cable--for optimal performance, Category 5e is recommended. The end node should be connected to any of the ports of the switch. Figure 4- 1. Switch connected to an End Node The Link/Act LEDs light green when the link is valid. A blinking green LED indicates packet activity on that port. The Speed LEDs indicate port speed and will light solid green for 1000 Mbps connections. They will remain off for 10 or 100 Mbps connections. 9 DGS-3024 Gigabit Ethernet Switch Manual Switch to Hub or Switch These connections can be accomplished in a number of ways using a normal cable. · · · A 10BASE-T hub or switch can be connected to the switch via a two-pair Category 3, 4, 5, or 5e UTP/STP cable. A 100BASE-TX hub or switch can be connected to the switch via a two-pair Category 5 or 5e UTP/STP cable. A 1000BASE-T switch can be connected to the switch via four-pair straight Category 5 or 5e UTP/STP cable. Figure 4- 2. Switch connected to a normal (non-Uplink) port on a hub or switch using a straight or crossover cable Switch to Core Router Switch This connection can be accomplished using the following fiber optic media: · · · · SFP Transceiver for 1000BASE-LX Single-mode fiber module (10km) SFP Transceiver for 1000BASE-SX Multi-mode fiber module (550m) SFP Transceiver for 1000BASE-LHX Single-mode fiber module (40km) SFP Transceiver for 1000BASE-ZX Single-mode fiber module (80km) 10 DGS-3024 Gigabit Ethernet Switch Manual Figure 4- 3. Switch connected by optical fiber cable to a Core Router Switch, with a server connected by crossover cable and a PC connected by a Category 3, 4, 5, or 5e UTP/STP cable ) 11 DGS-3024 Gigabit Ethernet Switch Manual 5 Web-Based Network Management Introduction The DGS-3024 offers an embedded Web-based (HTML) interface allowing users to manage the switch from anywhere on the network through a standard browser, such as Opera, Netscape Navigator/Communicator, or Microsoft Internet Explorer. The Web browser acts as a universal access tool and can communicate directly with the switch using the HTTP protocol. Your browser window may vary with the screen shots (pictures) in this guide. The Web-based management module and the Console program (and Telnet) are different ways to access the same internal switching software and configure it. Thus, all settings encountered in Web-based management are the same as those found in the console program. NOTE: This Web-based Management module does not accept Chinese language input (or other languages requiring 2 bytes per character). NOTE: The Web browser needs to be upgraded to the latest Java version (JavaTM Plug-in: version 1.5.0 or later). Login to Web Manager To begin managing your Switch, simply run the browser you have installed on your computer and point it to the IP address you have defined for the device. The URL in the address bar should read something like: http://123.123.123.123, where the numbers 123 represent the IP address of the Switch. Please note that the proxy for session connection should be turned off. NOTE: The Factory default IP address for the Switch is 10.90.90.90. In the page that opens, click on the Login to make a setup button: Figure 5- 1. Login button This opens the management module's user authentication window, as seen below. 12 DGS-3024 Gigabit Ethernet Switch Manual Figure 5- 2. Enter Network Password dialog box Leave both the User Name field and the Password field blank and click OK. This will open the Web-based user interface. The Switch management features available in the Web-based manager are explained below. Web-based User Interface The user interface provides access to various Switch configuration and management windows, allows you to view performance statistics, and permits you to graphically monitor the system status. Areas of the User Interface The figure below shows the user interface. The user interface is divided into three distinct areas as described in the table. Area 2 Area 3 Area 1 Figure 5- 3. Main Web-Manager window Area Area 1 Area 2 Function Select the folder or window to be displayed. The folder icons can be opened to display the hyperlinked menu buttons and subfolders contained within them. Presents a graphical near real-time image of the front panel of the Switch. This area displays the Switch's ports and expansion modules, showing port activity, duplex 13 DGS-3024 Gigabit Ethernet Switch Manual mode, or flow control, depending on the specified mode. Various areas of the graphic can be selected for performing management functions, including port configuration. Area 3 Presents switch information based on your selection and the entry of configuration data. NOTICE: Any changes made to the Switch configuration during the current session must be saved in the Save Configuration window (Maintenance Save Changes) or use the command line interface (CLI) command save. NOTE: Be sure to configure the user name and password in the User Account Management window (Management User Accounts) before connecting the Switch to the greater network. 14 DGS-3024 Gigabit Ethernet Switch Manual 6 Configuration The first Web Manager main folder is Configuration and includes the following windows and sub-folders: IP Address, Switch Information, Advanced Settings, Port Configuration, Port Mirroring, IGMP, Spanning Tree, Forwarding, VLANs, SNTP Setting, QoS, Link Aggregation, MAC Notification, System Log Server, Port Access Entity, and Static ARP Settings, as well as secondary windows. IP Address Figure 6- 1. Switch IP Settings window This window is used to determine whether the switch should get its IP Address settings from the user (Manual), a BOOTP server, or a DHCP server. If you are not using either BOOTP or DHCP, enter the IP Address, Subnet Mask, and Default Gateway of the switch. If you enable BOOTP, you do not need to configure any IP parameters because a BOOTP server automatically assigns IP configuration parameters to the switch. If you enable DHCP, a Dynamic Host Configuration Protocol request will be sent when the switch is powered up. Once you have selected a setting under Get IP From, click Apply to activate the new settings. The information is described as follows: Parameter Get IP From IP Address Subnet Mask Default Gateway VID Description There are three choices for how the switch receives its IP Address settings: Manual, BOOTP, and DHCP. The host address for the device on the TCP/IP network. The address mask that controls subnetting on your TCP/IP network. The IP address of the device--usually a router--that handles connections to other subnets and/or other TCP/IP networks. The VLAN ID number. 15 DGS-3024 Gigabit Ethernet Switch Manual Switch Information Figure 6- 2. Switch Information (Basic Settings) window This window is used to enter name, location, and contact information. Click Apply to activate the new settings. The information is described as follows: Parameter Device Type MAC Address Boot PROM Version Firmware Version Description A description of the switch type. The Ethernet address for the device. Also known as the physical address. Version number for the firmware chip. This information is needed for new runtime software downloads. Version number of the firmware installed on the switch. This can be updated by using the Download Firmware from TFTP Server window in the TFTP Services folder (Maintenance TFTP Services Download Firmware from TFTP Server). Version of the switch hardware. A user-assigned name for the switch. A user-assigned description for the physical location of the switch. Name of the person to contact should there be any problems or questions with the system. You may also want to include a phone number or extension. Hardware Version System Name System Location System Contact 16 DGS-3024 Gigabit Ethernet Switch Manual Advanced Settings Figure 6- 3. Switch Information (Advanced Settings) window The following fields can be set: Parameter Serial Port Logout Serial Rate Port Auto Baud Description This setting for the restart of the console is 2 Minutes, 5 Minutes, 10 Minutes, 15 Minutes, or Never. The default is 10 Minutes. Determines the serial port bit rate that will be used the next time the switch is restarted. Available speeds are 9600, 19,200, 38,400, and 115,200 bits per second. The default setting is 9600. This field specifies the length of time a learned MAC Address will remain in the forwarding table without being accessed (that is, how long a learned MAC Address is allowed to remain idle). To change this, type in a different value representing the MAC address age-out time in seconds. The MAC Address Aging Time can be set to any value between 0 and 14,400 min. The default setting is 5 min. This indicates if Internet Group Management Protocol (IGMP) Snooping is enabled on the switch. When enabled, this feature instructs the switch to read IGMP packets being forwarded through the switch in order to obtain forwarding information from them (learn which ports contain Multicast members). The switch's IGMP snooping state can be changed on the IGMP Snooping Settings window (Configuration IGMP IGMP Snooping). This indicates if a Telnet connection is currently enabled on the switch. Web-based management is Enabled by default. If you choose to disable this by selecting Disabled, you will lose the ability to configure the system through the web interface as soon as these settings are applied This indicates if RMON is enabled on the switch. 17 MAC Address Aging Time (0-14400 min) IGMP Snooping Telnet Status Web Status RMON Status DGS-3024 Gigabit Ethernet Switch Manual GVRP This indicates if Group VLAN Registration Protocol (GVRP) is enabled on the switch. GVRP is a protocol that allows members to dynamically join VLANs. The switch's GVRP settings can be changed on the GVRP Settings window (Configuration VLANs GVRP Settings). The algorithm that the Switch uses to balance the load across the ports that make up the port trunk group is defined by this definition. Choose MAC Source, MAC Destination, or MAC Src & Dest, (For further information, see the Link Aggregation section, under the Link Aggregation folder). The Switch's 802.1x function may be enabled by port; the default is Disabled. This field must be enabled to view and configure certain windows for 802.1x. More information regarding 802.1x, its functions and implementation can be found later in this section, under the Port Access Entity folder. Port-Based 802.1x specifies that ports configured for 802.1x are initialized based on the port number only and are subject to any authorization parameters configured. This allows you to enable or disable the System Log Global State. Link Aggregation Algorithm Switch 802.1x Syslog Global State 18 DGS-3024 Gigabit Ethernet Switch Manual Port Configuration Figure 6- 4. Port Configuration window To configure switch ports: 1. 2. Choose the port or sequential range of ports using the From and To pull-down menus. Use the remaining pull-down menus to configure the parameters described below: Description Toggle the State field to either enable or disable a given port or group of ports. Toggle the Speed/Duplex field to either select the speed and duplex/half-duplex state of the port. Auto denotes auto-negotiation between 10 and 100 Mbps devices, in full- or half-duplex. The Auto setting allows the port to automatically determine the fastest settings the device the port is connected to can handle, and 19 Parameter State Speed/Duplex DGS-3024 Gigabit Ethernet Switch Manual then to use those settings. The other options are Auto, 10M/Half, 10M/Full, 100M/Half, 100M/Full, and 1000M/Full. There is no automatic adjustment of port settings with any option other than Auto. Flow Control Displays the flow control scheme used for the various port configurations. Ports configured for full-duplex use 802.3x flow control, half-duplex ports use backpressure flow control, and Auto ports use an automatic selection of the two. The default is Disabled. Enable or disable MAC address learning for the selected ports. When Enabled, destination and source MAC addresses are automatically listed in the forwarding table. When learning is Disabled, MAC addresses must be manually entered into the forwarding table. This is sometimes done for reasons of security or efficiency. See the section on Forwarding for information on entering MAC addresses into the forwarding table. The default setting is Disabled. Learning Click Apply to implement the new settings on the Switch. Port Mirroring Figure 6- 5. Setup Port Mirroring window To configure a mirror port: 1. 2. 3. Select the Source Port from where you want to copy frames and the Target Port, which receives the copies from the source port. Select Ingress, Egress, or None and change the Status drop-down menu to Enabled. Click Apply to let the changes take effect. NOTE: You cannot mirror a fast port onto a slower port. For example, if you try to mirror the traffic from a 100 Mbps port onto a 10 Mbps port, this can cause throughput problems. The port you are copying frames from should always support an equal or lower speed than the port to which you are sending the copies. Also, the target port for the mirroring cannot be a member of a trunk group. Please note a target port and a source port 20 DGS-3024 Gigabit Ethernet Switch Manual cannot be the same port. IGMP Internet Group Management Protocol (IGMP) snooping allows the Switch to recognize IGMP queries and reports sent between network stations or devices and an IGMP host. When enabled for IGMP snooping, the Switch can open or close a port to a specific device based on IGMP messages passing through the Switch. In order to use IGMP Snooping it must first be enabled for the entire Switch on the Switch Information (Advanced Settings) window (Configuration > Advanced Settings). You may then fine-tune the settings for each VLAN by clicking the IGMP Snooping link in the Configuration folder. When enabled for IGMP snooping, the Switch can open or close a port to a specific multicast group member based on IGMP messages sent from the device to the IGMP host or vice versa. The Switch monitors IGMP messages and discontinues forwarding multicast packets when there are no longer hosts requesting that they continue. IGMP Snooping Use the Current IGMP Snooping Group Entries window to view IGMP Snooping settings. To modify the settings, click the Modify button of the VLAN ID you want to change. Figure 6- 6. Current IGMP Snooping Group Entries window Clicking the Modify button will open the IGMP Snooping Settings window, shown below: Figure 6- 7. IGMP Snooping Settings window 21 DGS-3024 Gigabit Ethernet Switch Manual The following parameters may be viewed or modified: Parameter VLAN ID VLAN Name Query Interval Max Response Time Robustness Value Description This is the VLAN ID that, along with the VLAN Name, identifies the VLAN the user wishes to modify the IGMP Snooping Settings for. This is the VLAN Name that, along with the VLAN ID, identifies the VLAN the user wishes to modify the IGMP Snooping Settings for. Allows the entry of a value between 1 and 65535 seconds, with a default of 125 seconds. This specifies the length of time between sending IGMP queries. Sets the maximum amount of time allowed before sending an IGMP response report. A value between 1 and 25 seconds can be entered, with a default of 10 seconds. A tuning variable to allow for subnetworks that are expected to lose a large number of packets. A value between 2 and 255 can be entered, with larger values being specified for subnetworks that are expected to lose larger numbers of packets. The default is 2 seconds. Specifies the maximum amount of time between group-specific query messages, including those sent in response to leave group messages. A value between 1 and 25. The default is 1 second. This is the maximum amount of time in seconds allowed for a host to continue membership in a multicast group without the Switch receiving a host membership report. The default is 260. This is the maximum amount of time in seconds a route is kept in the forwarding table without receiving a membership report. The default is 260. This specifies the maximum amount of time in seconds between the Switch receiving a leave group message from a host, and the Switch issuing a group membership query. If no response to the membership query is received before the Leave Timer expires, the (multicast) forwarding entry for that host is deleted. Choose Enabled to enable transmitting IGMP Query packets or Disabled to disable. The default is Disabled. This field can be toggled between Enabled and Disabled and enables or disables IGMP for the VLAN. The default is Disabled. Last Member Query Interval Host Timeout Route Timeout Leave Timer Querier State State Click Apply to implement the new settings. Click the Show All IGMP Group Entries link to return to the Current IGMP Snooping Group Entries window. Static Router Ports Entry Figure 6- 8. Current Static Router Ports Entries window 22 DGS-3024 Gigabit Ethernet Switch Manual Select an entry and click Modify to access the following window: Figure 6- 9. Static Router Ports Settings ­ Edit window The following parameters can be viewed or set: Parameter VID (VLAN ID) VLAN Name Member Ports Description This is the VLAN ID that, along with the VLAN Name, identifies the VLAN where the multicast router is attached. This is the name of the VLAN where the multicast router is attached. These are the ports on the Switch that will have a multicast router attached to them. Click Apply to implement the new settings, Click the Show All Static Router Port Entries link to return to the Current Static Router Port Entries window. Spanning Tree This Switch supports two versions of the Spanning Tree Protocol: 802.1d STP and 802.1w Rapid STP. 802.1w Rapid Spanning Tree The Switch implements two versions of the Spanning Tree Protocol, Rapid Spanning Tree Protocol (RSTP) as defined by the IEEE 802.1w specification and a version compatible with the IEEE 802.1d STP. RSTP can operate with legacy equipment implementing IEEE 802.1d, however the advantages of using RSTP will be lost. The IEEE 802.1w Rapid Spanning Tree Protocol (RSTP) evolved from the 802.1d STP standard. RSTP was developed in order to overcome some limitations of STP that impede the function of some recent switching innovations, in particular, certain Layer 3 functions that are increasingly handled by Ethernet switches. The basic function and much of the terminology is the same as STP. Most of the settings configured for STP are also used for RSTP. This section introduces some new Spanning Tree concepts and illustrates the main differences between the two protocols. Port Transition States An essential difference between the two protocols is in the way ports transition to a forwarding state and in the way this transition relates to the role of the port (forwarding or not forwarding) in the topology. RSTP combines the transition states disabled, blocking and listening used in 802.1d and creates a single state Discarding. Ports do not forward packets. In the STP port transition states disabled, blocking or listening or in the RSTP port state discarding, there is no functional difference, the port is not active in the network topology. Table 6-1 below compares how the two protocols differ regarding the port state transition. 23 DGS-3024 Gigabit Ethernet Switch Manual All twoe protocols calculate a stable topology in the same way. Every segment will have a single path to the root bridge. All bridges listen for BPDU packets. However, BPDU packets are sent more frequently - with every Hello packet. BPDU packets are sent even if a BPDU packet was not received. Therefore, each link between bridges is sensitive to the status of the link. Ultimately this difference results in faster detection of failed links, and thus faster topology adjustment. A drawback of 802.1d is this absence of immediate feedback from adjacent bridges. 802.1w RSTP Discarding Discarding Discarding Learning Forwarding 802.1d STP Disabled Blocking Listening Learning Forwarding Forwarding No No No No Yes Learning No No No Yes Yes Table 6- 1. Comparing Port States RSTP is capable of a more rapid transition to a forwarding state - it no longer relies on timer configurations - RSTP compliant bridges are sensitive to feedback from other RSTP compliant bridge links. Ports do not need to wait for the topology to stabilize before transitioning to a forwarding state. In order to allow this rapid transition, the protocol introduces two new variables: the edge port and the point-to-point (P2P) port. Edge Port The edge port is a configurable designation used for a port that is directly connected to a segment where a loop cannot be created. An example would be a port connected directly to a single workstation. Ports that are designated as edge ports transition to a forwarding state immediately without going through the listening and learning states. An edge port loses its status if it receives a BPDU packet, immediately becoming a normal spanning tree port. P2P Port A P2P port is also capable of rapid transition. P2P ports may be used to connect to other bridges. Under RSTP, all ports operating in full-duplex mode are considered to be P2P ports, unless manually overridden through configuration. 802.1d/802.1w Compatibility RSTP can interoperate with legacy equipment and is capable of automatically adjusting BPDU packets to 802.1d format when necessary. However, any segment using 802.1d STP will not benefit from the rapid transition and rapid topology change detection of RSTP. The protocol also provides for a variable used for migration in the event that legacy equipment on a segment is updated to use RSTP. The Spanning Tree Protocol (STP) operates on two levels: 1. 2. On the switch level, the settings are globally implemented. On the port level, the settings are implemented on a per user-defined group of ports basis. 24 DGS-3024 Gigabit Ethernet Switch Manual STP Switch Settings Figure 6- 10. Switch Spanning Tree Settings window The following parameters can be set: Parameter Spanning Tree Status Bridge Max Age (6 - 40 Sec) <20> Description Use the pull-down menu to enable or disable STP globally on the Switch. The default is Disabled. The Bridge Max Age may be set to ensure that old information does not endlessly circulate through redundant paths in the network, preventing the effective propagation of the new information. Set by the Root Bridge, this value will aid in determining that the Switch has spanning tree configuration values consistent with other devices on the bridged LAN. If the value ages out and a BPDU has still not been received from the Root Bridge, the Switch will start sending its own BPDU to all other switches for permission to become the Root Bridge. If it turns out that your switch has the lowest Bridge Identifier, it will become the Root Bridge. The user may choose a time between 6 and 40 seconds. The default value is 20. 25 DGS-3024 Gigabit Ethernet Switch Manual Bridge Hello Time (1 - 10 Sec) <2> The Bridge Hello Time can be set from 1 to 10 seconds. This is the interval between two transmissions of BPDU packets sent by the Root Bridge to tell all other switches that it is indeed the Root Bridge. This field will only appear here when STP or RSTP is selected for the STP Version. The Bridge Forward Delay can be from 4 to 30 seconds. Any port on the Switch spends this time in the listening state while moving from the blocking state to the forwarding state. The Bridge Priority for the switch can be set from 0 to 61440 seconds. Zero is equal to the highest Priority. This number is used in the voting process between switches on the network to determine which switch will be the root switch. A low number indicates a high priority, and a high probability that this switch will be elected as the root switch Use the pull-down menu to choose the desired version of STP to be implemented on the Switch. There are two choices: Stp Compatibility - Select this parameter to set the Spanning Tree Protocol (STP) globally on the switch. RSTP - Select this parameter to set the Rapid Spanning Tree Protocol (RSTP) globally on the Switch. TX Hold Count (1-10) <3> Forwarding BPDU Used to set the maximum number of Hello packets transmitted per interval. The count can be specified from 1 to 10. The default is 3. This field can be Enabled or Disabled. When Enabled, it allows the forwarding of STP BPDU packets from other network devices. The default is Enabled. Bridge Forward Delay (4 - 30 sec) <15 > Bridge Priority (0-61440) STP Version Click Apply to implement changes made. NOTE: The Bridge Hello Time cannot be longer than the Bridge Max Age. Otherwise, a configuration error will occur. Observe the following formulas when setting the above parameters: Max. Age = 2 x (Forward Delay - 1 second) Max. Age = 2 x (Hello Time + 1 second) 26 DGS-3024 Gigabit Ethernet Switch Manual STP Port Settings Figure 6- 11. STP Port Settings window The following fields can be set: Parameter From/To State Cost < 0 = Auto> Description A consecutive group of ports may be configured starting with the selected port. This drop-down menu allows you to enable or disable STP for the selected group of ports. The default is Enabled. This defines a metric that indicates the relative cost of forwarding packets to the specified port list. Port cost can be set automatically or as a metric value. The default value is 0(auto). 0 (auto) - Setting 0 for the external cost will automatically set the speed for forwarding packets to the specified port(s) in the list for optimal efficiency. Default port cost: 100Mbps port = 200000. Gigabit port = 20000. value 1-200000000 - Define a value between 1 and 200000000 to determine the external cost. The lower the number, the greater the probability the port will be chosen to forward packets. 27 DGS-3024 Gigabit Ethernet Switch Manual Priority <128> Migration A port priority can be set between 0 and 255. The lower the priority, the greater the probability the port will be chosen as the root port. The default is 128 seconds. Setting this parameter as "Yes" will set the ports to send out BDPU packets to other bridges, requesting information on their STP setting If the Switch is configured for RSTP, the port will be capable to migrate from 802.1d STP to 802.1w RSTP. RSTP can coexist with standard STP, however the benefits of RSTP are not realized on a port where an 802.1d network connects to an 802.1w enabled network. Migration should be set as Yes on ports connected to network stations or segments that are capable of being upgraded to 802.1w RSTP on all or some portion of the segment. Choosing the True parameter designates the port as an edge port. Edge ports cannot create loops, however an edge port can lose edge port status if a topology change creates a potential for a loop. An edge port normally should not receive BPDU packets. If a BPDU packet is received, it automatically loses edge port status. Choosing the False parameter indicates that the port does not have edge port status. Choosing the True parameter indicates a point-to-point (P2P) shared link. P2P ports are similar to edge ports, however they are restricted in that a P2P port must operate in full duplex. Like edge ports, P2P ports transition to a forwarding state rapidly thus benefiting from RSTP. A p2p value of false indicates that the port cannot have p2p status. Auto allows the port to have p2p status whenever possible and operate as if the p2p status were true. If the port cannot maintain this status, (for example if the port is forced to half-duplex operation) the p2p status changes to operate as if the p2p value were False. The default setting for this parameter is True. Edge P2P Click Apply to implement changes made. Forwarding Unicast Forwarding Open the Forwarding folder in the Configuration menu and click on the Unicast Forwarding link. This will open the Setup Static Unicast Forwarding Table window, as shown below: Figure 6- 12. Setup Static Unicast Forwarding Table window To add or edit an entry, define the following parameters and then click Add/Modify: Parameter Description 28 DGS-3024 Gigabit Ethernet Switch Manual VID (VLAN ID) MAC Address Allowed to go port The VLAN ID number of the VLAN on which the above Unicast MAC address resides. The MAC address to which packets will be statically forwarded. This must be a unicast MAC address. Allows the selection of the port number on which the MAC address entered above resides. Click Apply to implement the changes made. To delete an entry in the Static Unicast Forwarding Table, click the corresponding under the Delete heading. Multicast Forwarding The following window describes how to set up Multicast Forwarding on the Switch. Open the Forwarding folder and click on the Multicast Forwarding link to see the entry window below: Figure 6- 13. Static Multicast Forwarding Settings window The Static Multicast Forwarding Settings window displays all of the entries made into the Switch's static multicast forwarding table. Click the Add button to open the Setup Static Multicast Forwarding Table window, as shown below: Figure 6- 14. Setup Static Multicast Forwarding Table window The following parameters can be set: Parameter VID Multicast MAC Address Port Settings Description The VLAN ID of the VLAN the corresponding MAC address belongs to. The MAC address of the static source of multicast packets. This must be a multicast MAC address. Allows the selection of ports that will be members of the static multicast group and ports that are either forbidden from joining dynamically, or that can join the multicast group dynamically, using GMRP. The options are: 29 DGS-3024 Gigabit Ethernet Switch Manual None - No restrictions on the port dynamically joining the multicast group. When None is chosen, the port will not be a member of the Static Multicast Group. Egress - The port is a static member of the multicast group. Click Apply to implement the changes made. To delete an entry in the Static Multicast Forwarding Table, click the corresponding under the Delete heading. Click the Show All Multicast Forwarding Entries link to return to the Static Multicast Forwarding Settings window. VLANs Understanding IEEE 802.1p Priority Priority tagging is a function defined by the IEEE 802.1p standard designed to provide a means of managing traffic on a network where many different types of data may be transmitted simultaneously. It is intended to alleviate problems associated with the delivery of time critical data over congested networks. The quality of applications that are dependent on such time critical data, such as video conferencing, can be severely and adversely affected by even very small delays in transmission. Network devices that are in compliance with the IEEE 802.1p standard have the ability to recognize the priority level of data packets. These devices can also assign a priority label or tag to packets. Compliant devices can also strip priority tags from packets. This priority tag determines the packet's degree of expeditiousness and determines the queue to which it will be assigned. Priority tags are given values from 0 to 7 with 0 being assigned to the lowest priority data and 7 assigned to the highest. The highest priority tag 7 is generally only used for data associated with video or audio applications, which are sensitive to even slight delays, or for data from specified end users whose data transmissions warrant special consideration. The Switch allows you to further tailor how priority tagged data packets are handled on your network. Using queues to manage priority tagged data allows you to specify its relative priority to suit the needs of your network. There may be circumstances where it would be advantageous to group two or more differently tagged packets into the same queue. Generally, however, it is recommended that the highest priority queue, Queue 1, be reserved for data packets with a priority value of 7. Packets that have not been given any priority value are placed in Queue 0 and thus given the lowest priority for delivery. A weighted round robin system is employed on the Switch to determine the rate at which the queues are emptied of packets. The ratio used for clearing the queues is 4:1. This means that the highest priority queue, Queue 1, will clear 4 packets for every 1 packet cleared from Queue 0. Remember, the priority queue settings on the Switch are for all ports, and all devices connected to the Switch will be affected. This priority queuing system will be especially beneficial if your network employs switches with the capability of assigning priority tags. VLAN Description A Virtual Local Area Network (VLAN) is a network topology configured according to a logical scheme rather than the physical layout. VLANs can be used to combine any collection of LAN segments into an autonomous user group that appears as a single LAN. VLANs also logically segment the network into different broadcast domains so that packets are forwarded only between ports within the VLAN. Typically, a VLAN corresponds to a particular subnet, although not necessarily. VLANs can enhance performance by conserving bandwidth, and improve security by limiting traffic to specific domains. A VLAN is a collection of end nodes grouped by logic instead of physical location. End nodes that frequently communicate with each other are assigned to the same VLAN, regardless of where they are physically on the network. Logically, a VLAN can be equated to a broadcast domain, because broadcast packets are forwarded to only members of the VLAN on which the broadcast was initiated. 30 DGS-3024 Gigabit Ethernet Switch Manual Notes About VLANs on the DGS-3024 No matter what basis is used to uniquely identify end nodes and assign these nodes VLAN membership, packets cannot cross VLANs without a network device performing a routing function between the VLANs. The DGS-3024 supports IEEE 802.1Q VLANs. The port untagging function can be used to remove the 802.1Q tag from packet headers to maintain compatibility with devices that are tag-unaware. The Switch's default is to assign all ports to a single 802.1Q VLAN named "default." The "default" VLAN has a VID = 1. IEEE 802.1Q VLANs Some relevant terms: Tagging ­ The act of putting 802.1Q VLAN information into the header of a packet. Untagging ­ The act of stripping 802.1Q VLAN information out of the packet header. Ingress port ­ A port on a switch where packets are flowing into the Switch and VLAN decisions must be made. Egress port ­ A port on a switch where packets are flowing out of the Switch, either to another switch or to an end station, and tagging decisions must be made. IEEE 802.1Q (tagged) VLANs are implemented on the Switch. 802.1Q VLANs require tagging, which enables them to span the entire network (assuming all switches on the network are IEEE 802.1Q-compliant). VLANs allow a network to be segmented in order to reduce the size of broadcast domains. All packets entering a VLAN will only be forwarded to the stations (over IEEE 802.1Q enabled switches) that are members of that VLAN, and this includes broadcast, multicast and unicast packets from unknown sources. VLANs can also provide a level of security to your network. IEEE 802.1Q VLANs will only deliver packets between stations that are members of the VLAN. Any port can be configured as either tagging or untagging. The untagging feature of IEEE 802.1Q VLANs allows VLANs to work with legacy switches that don't recognize VLAN tags in packet headers. The tagging feature allows VLANs to span multiple 802.1Q-compliant switches through a single physical connection and allows Spanning Tree to be enabled on all ports and work normally. The IEEE 802.1Q standard restricts the forwarding of untagged packets to the VLAN the receiving port is a member of. The main characteristics of IEEE 802.1Q are as follows: · · · · Assigns packets to VLANs by filtering. Assumes the presence of a single global spanning tree. Uses an explicit tagging scheme with one-level tagging. 802.1Q VLAN Packet Forwarding Packet forwarding decisions are made based upon the following three types of rules: · · · Ingress rules - rules relevant to the classification of received frames belonging to a VLAN. Forwarding rules between ports - decides whether to filter or forward the packet. Egress rules - determines if the packet must be sent tagged or untagged. 31 DGS-3024 Gigabit Ethernet Switch Manual Figure 6- 15. IEEE 802.1Q Packet Forwarding 802.1Q VLAN Tags The figure below shows the 802.1Q VLAN tag. There are four additional octets inserted after the source MAC address. Their presence is indicated by a value of 0x8100 in the EtherType field. When a packet's EtherType field is equal to 0x8100, the packet carries the IEEE 802.1Q/802.1p tag. The tag is contained in the following two octets and consists of 3 bits of user priority, 1 bit of Canonical Format Identifier (CFI - used for encapsulating Token Ring packets so they can be carried across Ethernet backbones), and 12 bits of VLAN ID (VID). The 3 bits of user priority are used by 802.1p. The VID is the VLAN identifier and is used by the 802.1Q standard. Because the VID is 12 bits long, 4094 unique VLANs can be identified. The tag is inserted into the packet header making the entire packet longer by 4 octets. All of the information originally contained in the packet is retained. 32 DGS-3024 Gigabit Ethernet Switch Manual Figure 6- 16. IEEE 802.1Q Tag The EtherType and VLAN ID are inserted after the MAC source address, but before the original EtherType/Length or Logical Link Control. Because the packet is now a bit longer than it was originally, the Cyclic Redundancy Check (CRC) must be recalculated. Figure 6- 17. Adding an IEEE 802.1Q Tag Port VLAN ID Packets that are tagged (are carrying the 802.1Q VID information) can be transmitted from one 802.1Q compliant network device to another with the VLAN information intact. This allows 802.1Q VLANs to span network devices (and indeed, the entire network, if all network devices are 802.1Q compliant). Unfortunately, not all network devices are 802.1Q compliant. These devices are referred to as tag-unaware. 802.1Q devices are referred to as tag-aware. Prior to the adoption of 802.1Q VLANs, port-based and MAC-based VLANs were in common use. These VLANs relied upon a Port VLAN ID (PVID) to forward packets. A packet received on a given port would be assigned that port's PVID and then be forwarded to the port that corresponded to the packet's destination address (found in the Switch's forwarding 33 DGS-3024 Gigabit Ethernet Switch Manual table). If the PVID of the port that received the packet is different from the PVID of the port that is to transmit the packet, the Switch will drop the packet. Within the Switch, different PVIDs mean different VLANs (remember that two VLANs cannot communicate without an external router). So, VLAN identification based upon the PVIDs cannot create VLANs that extend outside a given switch (or switch stack). Every physical port on a switch has a PVID. 802.1Q ports are also assigned a PVID, for use within the Switch. If no VLANs are defined on the Switch, all ports are then assigned to a default VLAN with a PVID equal to 1. Untagged packets are assigned the PVID of the port on which they were received. Forwarding decisions are based upon this PVID, in so far as VLANs are concerned. Tagged packets are forwarded according to the VID contained within the tag. Tagged packets are also assigned a PVID, but the PVID is not used to make packet forwarding decisions, the VID is. Tag-aware switches must keep a table to relate PVIDs within the Switch to VIDs on the network. The Switch will compare the VID of a packet to be transmitted to the VID of the port that is to transmit the packet. If the two VIDs are different, the Switch will drop the packet. Because of the existence of the PVID for untagged packets and the VID for tagged packets, tag-aware and tag-unaware network devices can coexist on the same network. A switch port can have only one PVID, but can have as many VIDs as the Switch has memory in its VLAN table to store them. Because some devices on a network may be tag-unaware, a decision must be made at each port on a tag-aware device before packets are transmitted - should the packet to be transmitted have a tag or not? If the transmitting port is connected to a tag-unaware device, the packet should be untagged. If the transmitting port is connected to a tag-aware device, the packet should be tagged. Tagging and Untagging Every port on an 802.1Q compliant switch can be configured as tagging or untagging. Ports with tagging enabled will put the VID number, priority and other VLAN information into the header of all packets that flow into and out of it. If a packet has previously been tagged, the port will not alter the packet, thus keeping the VLAN information intact. The VLAN information in the tag can then be used by other 802.1Q compliant devices on the network to make packet-forwarding decisions. Ports with untagging enabled will strip the 802.1Q tag from all packets that flow into and out of those ports. If the packet doesn't have an 802.1Q VLAN tag, the port will not alter the packet. Thus, all packets received by and forwarded by an untagging port will have no 802.1Q VLAN information. (Remember that the PVID is only used internally within the Switch). Untagging is used to send packets from an 802.1Q-compliant network device to a non-compliant network device. Ingress Filtering A port on a switch where packets are flowing into the Switch and VLAN decisions must be made is referred to as an ingress port. If ingress filtering is enabled for a port, the Switch will examine the VLAN information in the packet header (if present) and decide whether or not to forward the packet. If the packet is tagged with VLAN information, the ingress port will first determine if the ingress port itself is a member of the tagged VLAN. If it is not, the packet will be dropped. If the ingress port is a member of the 802.1Q VLAN, the Switch then determines if the destination port is a member of the 802.1Q VLAN. If it is not, the packet is dropped. If the destination port is a member of the 802.1Q VLAN, the packet is forwarded and the destination port transmits it to its attached network segment. If the packet is not tagged with VLAN information, the ingress port will tag the packet with its own PVID as a VID (if the port is a tagging port). The switch then determines if the destination port is a member of the same VLAN (has the same VID) as the ingress port. If it does not, the packet is dropped. If it has the same VID, the packet is forwarded and the destination port transmits it on its attached network segment. This process is referred to as ingress filtering and is used to conserve bandwidth within the Switch by dropping packets that are not on the same VLAN as the ingress port at the point of reception. This eliminates the subsequent processing of packets that will just be dropped by the destination port. 34 DGS-3024 Gigabit Ethernet Switch Manual Default VLANs The Switch initially configures one VLAN, VID = 1, called "default." The factory default setting assigns all ports on the Switch to the "default." Packets cannot cross VLANs. If a member of one VLAN wants to connect to another VLAN, the link must be through an external router. NOTE: If no VLANs are configured on the Switch, then all packets will be forwarded to any destination port. Packets with unknown source addresses will be flooded to all ports. Broadcast and multicast packets will also be flooded to all ports. An example is presented below: VLAN Name System (default) Engineering Marketing Finance Sales VID 1 2 3 4 5 Switch Ports 5, 6, 7, 8, 21, 22, 23, 24 9, 10, 11, 12 13, 14, 15, 16 17, 18, 19, 20 1, 2, 3, 4 Table 6- 2. VLAN Example - Assigned Ports VLAN and Trunk Groups The members of a trunk group have the same VLAN setting. Any VLAN setting on the members of a trunk group will apply to the other member ports. NOTE: In order to use VLAN segmentation in conjunction with port trunk groups, you can first set the port trunk group(s), and then you may configure VLAN settings. If you wish to change the port trunk grouping with VLANs already in place, you will not need to reconfigure the VLAN settings after changing the port trunk group settings. VLAN settings will automatically change in conjunction with the change of the port trunk group settings. Static VLAN Entry In the Configuration folder, open the VLANs folder and click the Static VLAN Entry link to open the following window: 35 DGS-3024 Gigabit Ethernet Switch Manual Figure 6- 18. 802.1Q Static VLANs window The 802.1Q Static VLANs window lists all previously configured VLANs by VLAN ID and VLAN Name. To delete an existing 802.1Q VLAN, click the corresponding button under the Delete heading. To create a new 802.1Q VLAN, click the Add button in the 802.1Q Static VLANs window. A new window will appear, as shown below, to configure the port settings and to assign a unique name and number to the new VLAN. See the table below for a description of the parameters in the new window. Figure 6- 19. 802.1Q Static VLANs window (Add) To return to the Current 802.1Q Static VLANs Entries window, click the Show All Static VLAN Entries link. To change an existing 802.1Q VLAN entry, click the Modify button of the corresponding entry you wish to modify. A new window will appear to configure the port settings and to assign a unique name and number to the new VLAN. See the table below for a description of the parameters in the new window. 36