IBM 8270 AND 8272 LAN SWITCH RELEASE NOTES - VERSION 4.0.3

Edited JUL-98

This set of release notes provides specific information for software release 4.0.3 for the IBM 8270 and 8272 LAN Switch Products. It documents important operating environment considerations.

Release 4.0.3A supports the following products:

Release 4.0.3B supports Detailed instructions are contained in the Planning and Installation Guide shipped with the product. These guides are titled:











LATEST RELEASE LEVEL OF SOFTWARE

 If the publications package that came with the product contains a set of release notes and diskette inside the shrink-wrapped package, they may be down-level and should be discarded. This set of release notes and diskette are the latest level as of the manufacturing date of your switch. Any updates to the release notes and switch software will be posted on the Internet and can be obtained using the World Wide Web URL:

http://www.networking.ibm.com/support

It is important to check the Web site to ensure that you are using the latest level of software.


NEW FEATURES OF THE IBM 8270 AND 8272 LAN SWITCH SOFTWARE


ATM UFC SOFTWARE COREQUISITES


PROBLEMS FIXED IN THE 8270 AND 8272 LAN SWITCH SOFTWARE


KNOWN PROBLEMS / ANOMALIES / DESIGN POINTS

  1. If an MSS Client or Domain Client is configured to support Lan Network Manager, Invalid Port Entry found messages may appear in the Message Log Information. This does not cause any functional problems.

  2. The recommended procedure for terminating telnet sessions is the <ctrl-b> key sequence.

  3. On some emulators, console sessions through the serial port may drop after an extended period of time, if hardware flow control has been enabled on the switch. The connection is usually re-established by disconnecting and reconnecting the s/p cable. To avoid this problem, be sure the hardware flow control is disabled in the switch's Serial Link Configuration and that your emulator configuration conforms to the set up suggestions that are documented in the Planning and Installation Guide.

  4. The ATM feature card should only be installed in slot 1 of an 8272 LAN Switch Module FC 5208 or FC 6208, and only in slot 1 or 3 of a FC 5308 or FC 6308.

  5. After making configuration changes in a switch with two ATM LECs attached to the same ELAN, the switch should be reset to ensure network stability.

  6. If you are migrating from a Release 2.x level of code to a Release 3.x of code or higher, you MUST serially download the code the first time. After the switch has been rebooted with the new code then you can use the TFTP download for future code updates.

  7. If you fail to upgrade the port microcode when you update to this release level all of your ports will be placed into Store and Forward mode to help the main code coexist with the old port microcode.

  8. If you attempt to migrate to a previous level of code (from 4.x to 3.x for example) you must do the following:

  9. The maximum size frame supported by the switch is 4540 bytes. Frames larger than this will be aborted. This might require special setup by your network administrator.

  10. The introduction of transparent switching into a token ring environment can reveal latent conditions that are masked when only source route bridges are used to interconnect rings. The token ring frame format includes status information bits that have been used improperly by some network adapters or protocols. The usage of these bits has varied within the token ring industry during the past few years. The following problems have been attributed to the improper use of these bits:

    1. Some Level 2 protocol drivers or applications are known to improperly rely upon the frame status information as verification that the frame has been received by another station. IBM has supplied new protocol drivers to replace IBM-developed token ring drivers that have this defect. However, some users may not wish to upgrade their drivers at this time or may have non-IBM drivers with this mode of operation.

    2. Some stations report or log a soft error each time a frame is received based on an address match and the status information. The condition that is being reported is no longer a true indication of an error condition and should be ignored.

    The IBM 8272 port logic copies all frames on a ring in making the decision to forward or not forward a frame. The default settings will cause the IBM 8272 to SET the frame status bits on all data frames that it copies. This will avoid the need to update the protocol drivers that are expecting these bits to be set. However, this default may cause some devices to report and/or log excessive soft errors.

    If your network management applications indicate an increase in soft error reports when the 8272 switch is installed, please contact an IBM service representative at 1-800-426-7299, call path 4, 6, 3 (In Canada, call 1-800-565-3344.) The problem can be resolved through configuration options.

  11. The token adapter for the IBM 9221 (ES/9000) Processor will not open when directly attached to an 8272 port. You must use an MSAU such as the IBM 8228 Token Ring Network Multistation Access Unit or the IBM 8230 Token Ring Network Controlled Access Unit.

  12. You must manually configure the 8272 switch port if you connect to other manufacturers' switch ports that are configured for fixed, full-duplex-only operation, and that conform to the Dedicated Token Ring Draft Standard, Version 3. If your installation has such a configuration, refer to Chapter 4, "Configuration," in the section titled "Configuring Ports," in the planning and installation guide.

  13. If you experience difficulty opening Telnet sessions with the switch, or get error messages concerning terminal types, check the options for your Telnet client. Make sure that the terminal type is set to vt100, vt102, or vt220. If you are running Telnet from a command line, there is usually an option that allows you to choose what terminal type to use.

  14. Console arrow keys are unreliable when using a slow communication device (< 9600 baud). In this case, use the <TAB> key to select the console options.

  15. The 8272 provides an SNMP agent for management from an SNMP manager. The 8272 will allow LAN Network Manager LLC frames to flow through the switch so that communication to existing 8230s and source route bridges will be maintained. Some error reporting functions and ring map functions might be lost for the rings attached to the switch.

  16. When defining a Token Pipe Configuration, ensure that both ports of each interconnected pair have compatible configurations. The suggested configuration is "Auto-Confg" for Config Type and "FIX-16" for Speed.

  17. When a switch port configured in Auto-Detect with Ring Speed Adjust enabled (RSA16 or RSA4) discovers a connection to shared media, it will open and insert into the ring. If the open returns with an indication that the port is the first station to enter the ring, it will close. This is also true for ports configured in Fixed-Adapter mode with RSA enabled. This algorithm is analogous to that of IBM's auto-sensing adapters which dictates that an adapter that is capable of speed adjustment must have some other station on the ring (typically a server) from which it can sense the speed.

    If you want to have switch ports that are attached to shared media set the ring speed, you must change the default configuration of Auto-RSA16 to either Auto-Fix16, Auto-Fix4, or force the configuration to Adapter mode with Fix16 or Fix4 speed. If you use the 8272's Ring Speed Adjust feature you will need to set the ring speed for segmented rings.

  18. To ensure a directly connected FDX station always connects at 16 Mbps, you should manually set the station's adapter to a Fixed-16 mode of operation. Otherwise, there is a small possibility that a directly attached station that implements IBM's auto-speed algorithm, when connected to an 8272 port that is configured in Auto-Detect mode, will make its connection at 4 Mbps.

  19. Make the following corrections to the Planning and Installation Guide:

    Page 8-5, Figure 8-4:

  20. MIB Browser display errors of OCTET STRING objects. Under certain conditions, some MIB Browsers including the IBM NetView/6000 MIB Browser will incorrectly interpret the value of an OCTET STRING. The OCTET STRING may be printable ASCII characters. For example, the hexadecimal value of "41" is displayed as an "A".

    This can affect the following objects:

    8272 Private MIB OCTET STRINGs

    DTRC MIB OCTET STRINGs:

    RFC1213 OCTET STRINGs

    RFC1231 OCTET STRINGs

    RFC1493 OCTET STRINGs

    RFC1573 OCTET STRINGs

    RFC1695 OCTET STRINGs

    LEC MIB OCTET STRINGs

    DISCOVERY MIB OCTET STRINGs

  21. Most SNMP MIB Browers cannot create a new MIB table entry. This can affect the following tables:

    8272 Private MIB

    MAC filter entries can be created by a native SNMP SET request, network management application such as the IBM Nways Manager, a console session or a Telnet session.

  22. The following two notes should be added to the symptoms and procedures in Table 7-1 on page 7-3 of the Planning and Configuration Guide for the 8270:

    1. If all LEDs are on, the +5V-A fuses are open. See "Obtaining Service" on page 7-1.

    2. If the I (green) LED on the Token Ring Processor card is on and the console displays the message, "Invalid port access," the +5V-B or +5V-C fuses are open. See "Obtaining Service on page 7-1.

  23. The references to Security on ports 1-1 through 4-4 in Figures 4-20 and 4-21 in the 8272 Planning and Installation Guide do not apply to the ATM UFC.

  24. When IEEE 802.1d spanning tree is active, a port within that domain will require several seconds to make the transition from the blocking state to the forwarding state when the port is initially activated (e.g., joins an existing ring or activates a dedicated link). Some client or server applications may attempt to establish session activity during this time, resulting in error messages indicating a connection failure. These applications should be configured to wait at least 30 seconds after the LAN link is active before attempting to establish session activity. This delay can be reduced by modifying the 802.1d spanning tree default parameters.

  25. The dtrc.mib DESCRIPTION for the dtrCRFPortEnable object should be changed to: The enable/disable status of the CRF Port. This control can be used to disable a port.

    When you WRITE, the configuration is changed.

    When you READ, the data returned is the current operational state of the CRF Port, not the configuration.

  26. When the ATM UFC is to be used in a network with source-routed frames it is recommended that the LAN ID be configured in the switch, using the Source Route Configuration panel. If the LAN ID is not configured, and the switch learns the LAN ID (from explorer traffic on the network) the ATM LEC resets, disrupting any existing traffic.

  27. Data directed to one of the switch's own IP addresses cannot cross the internal bridge. In other words, the management station should use the IP address associated with the domain that is on its side of the internal bridge.

  28. The following objects defined by RFC1757 and rFC1513 always return a value of zero and cannot be used as an Alarm Variable:



8260/8265 SPECIFIC INFORMATION

  1. For installations of the 8272 LAN Switch Modules FC 5208 and FC 5308, the recommended software level for the 8260 ATM Control Point and Switch Module (CPSW) is v.3.1.8 or higher.

  2. For installations of the 8272 LAN Switch Modules FC 5208 and FC 5308, the recommended software level for the 8265 ATM Control Point and Switch Module (CPSW) is v.3.3.2 or higher.

  3. 8272 LAN Switch Module derives its power and cooling from the 8260 Hub.

  4. To install a Universal Feature Card (UFC) AFTER the LAN Switch Module has already been installed in an 8260 Hub, remove the Switch Module from the Hub in order to power OFF the module prior to installing the UFC. Then, beginning with step 2, follow the instructions contained in the Planning and Installation Guide, shipped with the specific UFC, in the section "Installing a Universal Feature Card."

  5. In configurations where FC 5208 or FC 6208 is inserted in positions 16 and 17 of an 8260 or where FC 5308 or FC 6308 is inserted in positions 15, 16 and 17 of an 8260, potential mechanical interference can occur when certain Universal Feature Cards (UFCs) are inserted in position 17. It is best to avoid position 17 when installing the 8272 LAN Switch Modules. If this can not be avoided, the UFC can be inserted with care.



2-PORT TOKEN RING FIBER UFC-SPECIFIC INFORMATION

  1. The 2-Port Fiber Token Ring UFC requires Release 2.0 or higher of the 8272 microcode.

  2. The 2-Port Fiber Token Ring UFC supports two pairs of multimode fiber connections via ST-type Optical Transmitter and Receiver ports.

  3. The two ST connectors marked TX of the 2-Port Fiber Token Ring UFC send 850 nM infrared light to an attached device.

  4. The two ST connectors marked RX of the 2-Port Fiber Token Ring UFC detect 850 nM infrared light from an attached device.

  5. The 2-Port Fiber-Token Ring UFC operates in a RI/RO- compatible attachment mode only. (802.5J is not supported at this time).

  6. Both ports of the 2-Port Fiber Token Ring UFC are compatible with either the RI or the RO ports of an IBM 8230 Token Ring Concentrator.

  7. If both the RI and RO of an attached device (such as an 8228, 8230, 8260) or a series of devices are connected to a single 8272 switch, spanning tree must be enabled. (Multiple connections to a single ring cannot be supported without the use of spanning tree).

  8. When connecting one 8272 to another 8272 using the 2-Port Fiber Token Ring UFC, one end of the fiber connection must be manually configured as an 'ADAPTER,' and the other end of the fiber connection must be manually configured as a 'PORT'. (Use the port configuration tables of the 8272.)



FILES ON THE DISKETTES AND SOFTWARE DOWNLOAD PROCEDURES