I recently had an incident where immediately after issuing the "no ip helper-address" command on a 6506 switch, the switch became unresponsive and traffic reached the standby switch. Some colleagues have speculated that this was caused by the command, or my failure to specify an ip address in the command (I wanted to remove the single ip helper-address from the interface, or because I ssh'd to the switch via the standby ip address.
I have no doubt that there is a link between running the command and a failure happening. However, I'd like to know if anyone thinks a failover situation is likely when running the above command.
If it isn't a direct cause of running the command, any suggestions on how to figure out what caused the failover? We recovered the switch by reloading.