Cisco Bug: CSCta84645 - CPU hog on SSM line card caused due to heartbeat failure
Mar 08, 2018
- Cisco MDS 9000 Series Multilayer Switches
Known Affected Releases
Symptom: The SSM module reloaded due to heartbeat failure with supervisor. Conditions: While the logs available were not sufficient to conduct a definitive RCA, Cisco has elaborated an hypothesis on what the issue could be. By looking at the available logs, we have reconstructed a set of events that could possibly lead to this situation. The following set of events could have lead to the Module heartbeat failure: 1.A large number of SCSI device server requests are outstanding at SANTap (these are non Read/Write commands that need to be processed in the "control path); 2.The zones changes or connectivity issues lead to host logouts from the SANTap DVTs. 3.Upon host logouts, ISAPI service layer tries to cleanup all the pending SCSI device server requests and this clean up could lead to prolonged high IPC activity between CPP (Control path processor) and DPP (Data path processor). 4.In this situation, the SSM CPU can become too busy to heartbeat with the Supervisor. This will lead to HB failure, with the SSM module getting reloaded by the supervisor.
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.
Bug Details Include
- Full Description (including symptoms, conditions and workarounds)
- Known Fixed Releases
- Related Community Discussions
- Number of Related Support Cases