Core issue
When the interface Command-Line Interface (CLI) wrr-queue queue-limit command is issued on a Cisco Catalyst 3550 switch with high traffic, certain queue-limit values can cause the switch to reset.
This can happen when there is a high rate of traffic that runs on the port, and the queue-limits are set to extreme values (for example, 1 100 100 100). In most cases, there is also a configured bandwidth value of 0 (as in wrr-queue bandwidth 0 65536 65536 65536).
Resolution
In most cases, if the configured bandwidth of 0 is changed to 1 (as in wrr-queue bandwidth 1 65536 65536 65536), the reset is prevented.
In order to completely avoid this problem, perform these steps:
- Shutdown the interface.
- Apply the CLI wrr-queue queue-limit command.
- Issue the no shutdown command on the interface.
Also, any version later than 12.1(13)EA1 for the 3550 hardware platform contains a resolution for this issue.
Refer to the release notes of Cisco bug ID CSCdx68750 for additional details.