Operating instructions

Appendix A. Hints and tips 237
• One version that has been known to
not exhibit this issue (although it has the port
down issue previously discussed) is tg3.c:v3.6RH (June 12, 2004).
Note that after installing a working tg3 driver you will still have to perform a shut and no
shut on the interface on the IGESM that was placed in err-disable by the faulty tg3 driver,
to bring the interface back up.
Possible issues with Hyperterm when using the console port
When connecting to the IGESM via a serial cable and the IGESM’s console port, sometimes
the user can see messages coming out from the port but is unable to enter any information.
(Pressing the Enter key does not result in a command prompt for entering commands.) This
issue has been seen most often when using Hyperterm with XP, but has been observed at
least once with Hyperterm and W2K.
Some suggestions that should ensure proper operation if you encounter this issue:
򐂰 Set flow control to none in hyperterm (usually works).
򐂰 Upgrade to the free, full version of Hyperterm (always works).
򐂰 Use a terminal emulator other than Hyperterm (always works).
Default Etherchannel load balancing may not be optimal
The default Etherchannel load balance setting (based on source MAC address) has been
found to result sometimes in outbound traffic primarily using only a single uplink to carry
traffic. This is hardly efficient when you have two or more outbound links that could be used in
the Etherchannel bundle. New options for Etherchannel load balancing are available with
12.1(14)AY4 and later that enable you to set the load balance to any of these:
򐂰 Source or destination MAC
򐂰 Source
and destination MAC (XOR)
򐂰 Source or destination IP (also know as SIP/DIP)
򐂰 Source
and destination IP (XOR)
An example of setting the Etherchannel load balance based on an XOR of the source and
destination MAC address (more likely than the default to produce the desired load balancing):
port-channel load-balance src-dst-mac
This global command sets outbound load balancing for all Etherchannels on a given IGESM.
Control of the IGESM IP address information
Under Management Module default configurations, the IP address, mask, and default
gateway of the IGESM are controlled by the Management Module. Therefore, if you attempt to
change this information directly on the IGESM, the information changes only temporarily and
reverts to the Management Module assigned IP information on the next IGESM reboot, the
next Management Module reboot, or the next time someone
saves the IP information for the
IGESM on the Management Module.
To give at least partial control of the this information over to the IGESM, perform these steps:
1. On Management Module, Advanced settings, set Preserve new IP configuration during
all resets to Disabled and click Save.