________________________________________________________________________________ Superstack® 3 Switch 4400 Series - Software Version 2.21 This document provides the following information: 1. Legal rights 2. New features in this release 3. Information about other 3Com products affected 4. Enhancements and fixes for known faults 5. Recommendations when using this release 6. Known problems with this release 7. Documentation errors and omissions 8. Network management software support 9. Upgrading this release 10. 3Com's World Wide Web site ________________________________________________________________________________ 1. Legal rights IMPORTANT: READ THIS BEFORE INSTALLING OR USING THIS SOFTWARE You should carefully read the terms and conditions of the Software License Agreement. This text is contained in a file called !license.txt. Your legal rights are defined therein. USE OF THIS SOFTWARE INDICATES THAT YOU ACCEPT SUCH TERMS AND CONDITIONS. IF YOU DO NOT AGREE WITH SUCH TERMS AND CONDITIONS, DO NOT USE THIS SOFTWARE. ________________________________________________________________________________ 2. New features in this release The version 2.21 agent feature set is a compatible superset of that provided by all previous versions of this agent. This agent provides support for the following: SuperStack 3 Switch 4400 (24-port) (3C17203) SuperStack 3 Switch 4400 (48-port) (3C17204) SuperStack 3 Switch 4400 SE (24-port) (3C17206) ________________________________________________________________________________ 3. Information about other 3Com products affected N/A ________________________________________________________________________________ 4. Enhancements and Fixes for known faults The following known faults in the software agent have been fixed in the version 2.21 software agent: - A 24 port unit will reset approximately every 104 days and a 48 port unit will reset approximately every 208 days. This has been resolved. - When a port has rapid spanning tree enabled and the link connected to that port goes down and then quickly back up, the port could be left in the spanning tree 'blocking' state. This has been fixed so that the port will revert to its correct spanning tree state. - Further protection against SNMP denial of service attacks. - The 4400 responded to UDP multicast packets to the ALL ROUTERS IP address (224.0.0.2) with a "Destination Unreachable" ICMP packet (excepting IGMP packets). This could add unnecessary ICMP packets to a network when certain other protocols were being used (e.g. the CISCO HSRP protocol). ________________________________________________________________________________ 5. Recommendations when using this release 3Com strongly recommends that you upgrade all Switch 4400 (24-port) units which are running version 1.x software agent to version 2.x software agent. If you want to create a mixed stack of Switch 4400 units (24-port and 48-port), you must first upgrade all Switch 4400 (24-port) units in the stack which are running version 1.x software agent to version 2.x software agent. You can then add Switch 4400 (48-port) units to the stack. CAUTION: Network problems may occur if you do not upgrade all Switch 4400 (24-port) units in a stack to version 2.x software agent. - TFTP Upgrades Note that when initiating a TFTP upgrade using the Web interface or CLI, if an incorrect TFTP server IP address or software upgrade filename is entered you will not be able to correct the IP address or filename until the TFTP upgrade operation has timed out. The default time out period is 5 minutes. You can avoid the 5 minute time out period by initialising the unit or stack. Use the 'system control initalize' CLI command to do this if necessary. - Configuring Link Aggregations When creating an aggregation between two systems the ports in the aggregation must not be physically connected together until the aggregation has been correctly configured at both ends of the link. Failure to configure the aggregation at both ends before physically connecting the ports can result in a number of serious network issues such as lost packets and network loops. - Stacking Units Switch 4400 units can be stacked together and then treated as a single manageable unit with one IP address. Any combination of 24-port and 48-port units is allowed in a single stack, as long as the total number of front panel ports does not exceed the limit of 192 ports. - Roving Analysis Roving analysis is supported in: - a standalone Switch 4400 (24-port) unit - a single Switch 4400 (24-port) unit within a stack of Switch 4400 units - a standalone Switch 4400 (48-port) unit Roving analysis is not supported: - across a stack of Switch 4400 units - in a single Switch 4400 (48-port) unit within a stack of Switch 4400 units - Replacing Expansion Modules When an expansion module is replaced by another module of a different type, the configuration of the expansion module will not be completely reset to factory defaults. Specifically the following module associated parameters will not be reset: - Static addresses - Resilient links - IGMP router ports - Spanning Tree port data - Half-duplex flow control 3Com recommends that all module configuration parameters should be reviewed after an expansion module has been replaced. - Adding Units to the Stack 3Com recommends that you initialize a Switch 4400 unit that has previously been used elsewhere in your network before you add it to an existing stack. If you do not initialize the unit, problems may be caused by conflicting Switch configurations. ________________________________________________________________________________ 6. Known problems with this release - Half-duplex flow control (backjamming) cannot be enabled or disabled on a per port basis. If any port on a specific unit is reconfigured, all half-duplex ports on that unit will be changed to the new configuration. - IGMP querying is disabled by default due to potential interoperability issues with core products that do not follow the lowest IP address election method. Refer to Chapter 3 "Using Multicast Filtering" of the Implementation Guide for more information about this method. If you wish to run multicast sessions in a network that does not contain any IGMP routers (or queriers), you can configure the Switch 4400 to automatically negotiate with compatible devices on VLAN 1 to become the querier. Use the bridge multicastFilter igmp queryMode CLI command. The Switch 4400 is compatible with any device that conforms to the IGMP v2 protocol. - IP multicasts will only be forwarded within a VLAN if an IGMP router is present in that VLAN. - The Switch Database is not cleared for Aggregated Links on non- master units in a stack. If Spanning Tree blocks a port then the Switch Database is cleared so that a new entry can be learnt. In a stack- wide Aggregated Link configuration that is blocked, the Switch Database is only cleared on one of the units in the stack. This means that traffic is not forwarded because it is sent down a blocked port. Loss of connectivity will occur until either the address is re- learnt against another port or the learned entries are removed (aged out) from the Switch Database. - Auto-MDIX mode is not available if auto-negotiation is disabled on a port. That port will only operate in MDI mode. - If Webcache Redirection is enabled and you upgrade the software of the units in a stack, the flow of HTTP traffic through the stack can be blocked. 3Com recommends that you disable Webcache Redirection on each unit before you upgrade the stack and re-enable it when all of the units have been upgraded. You can use the 'feature cacheConfig disableCache' CLI command or the 'System > Cache Config > Modify Cache' Web interface operation to disable Webcache Redirection. Alternatively you can reset the entire stack after the software upgrade has been completed. - When setting up a SLIP IP address and an IP address for the unit you must ensure that the assigned IP addresses are different. - If you use Netscape to manage your Switch you may experience problems when trying to change the user password. 3Com recommends that if you use Netscape and you need to change the password you do so via the CLI command. To do this from the Web interface Device View, use the System > Telnet > Connect operation to start a Telnet connection and then use the security device user modify CLI command. - If the error "The previous command window is still active" is displayed when using the Web interface, you must close that window before you can select another operation. You should then press Reload (Netscape) or Refresh (Internet Explorer) in your Web browser. - The Switch 4400 Web interface can only be accessed by any of the following Web browsers: - Microsoft Internet Explorer v4.0 - Microsoft Internet Explorer v5.0 - Microsoft Internet Explorer v5.5 - Netscape Communicator v4.5 - Netscape Communicator v4.6 - Netscape Communicator v4.7 - The Switch 4400 Web interface can be accessed on any of the following PC operating systems: - Microsoft Windows 95 - Microsoft Windows 98 - Microsoft Windows NT v4.0 - Microsoft Windows 2000 - An incompatibility exists in the default settings for Link Aggregation between the Switch 4400 and the following 3Com products: - Switch 4007 - Switch 3900 - Switch 9300 - CoreBuilder 9000 family - CoreBuilder 9400 - CoreBuilder 3500 - The products listed above disable auto-negotiation when a port is added to an aggregated link (trunk). In order for link aggregation (trunking) to work, ports at either end of an aggregated link (trunk) must be identically configured. To resolve the incompatibility, you must complete the following steps: 1. On any of the switches listed, you must disable TCMP on a trunk (aggregated link) that connects to a Switch 4400 Series, as TCMP is not supported on the Switch 4400 Series. 2. You must disable auto-negotiation on all ports on the Switch 4400 Series that you want to place in an aggregated link before you place them in the aggregated link. This will result in 10/100 Mbps ports being set to half duplex mode. Gigabit and 100BASE-FX ports will be set to full duplex mode. 3. The Switch 4400 does not support the aggregation of half duplex links. You must ensure that all 10/100 ports that you want to aggregate are configured to full duplex mode on both link partners. Refer to the Management Interface Reference Guide on the CD-ROM that accompanies the Switch 4400 Series for more information about configuring aggregated links. ________________________________________________________________________________ 7. Documentation errors and omissions N/A ________________________________________________________________________________ 8. Network Management software support 3Com Network Supervisor provides powerful yet easy-to-use network management. Focused on the needs of small to medium enterprises, it enables users to take control of their network. In particular it allows extremely simple configuration of Quality of Service (QoS) on SuperStack 3 Switch 4400's to enforce traffic prioritisation across the network. To download the latest 3Com Network Supervisor and Service Pack please visit: http://www.3com.com/tns/ For HP OpenView users the Superstack Switch 4400 (and all other 3Com managed products) are fully supported by the 3Com Integration Kit for HP OpenView (3C15300). ________________________________________________________________________________ 9. Upgrading this release The management software can be upgraded by using a TFTP Server or by using the Management Software Upgrade Utility supplied with your Switch. - If you have downloaded the management software designed for a TFTP Server upgrade, place the file s3m02_21.bin in the appropriate directory on the Server. - If you have downloaded the management software designed for a serial upgrade using the Management Software Upgrade Utility, place the file s3m02_21.bin in a directory accessible by the PC running the utility. For more information, refer to the Management Guide supplied with your Switch. ________________________________________________________________________________ 10. 3Com's World Wide Web site Access the latest networking information on the 3Com Corporation World Wide Web site by entering our URL into your Internet browser: http://www.3com.com/ ________________________________________________________________________________ (R) means registered trademark. (TM) means trademark. 3Com and SuperStack are registered trademarks of 3Com Corporation. Other trademarks are the property of their respective owners. Document Number: DRA1720-3BAA04 Issued: August 2002 Copyright (c) 2002 3Com Corporation. All Rights Reserved.