Symptom
Customer reported seeing VOUT OV/UV/SHUT alarms from time to time. The alarms got cleared by itself
Conditions
No particular condition. The issue is only observed on systems with DC PSUs.
Workaround
The alarms are difficult to reproduce hence the RC is still unknown. A workaround is provided by this DDTS:
1. Monitor PSU device accesses to determine if there is any concurrent race condition which might cause the issue.
2. Based on the logs from the field, the alarm went away in the next poll (5 seconds per poll). Workaround is to soak the alarms for 5 seconds before declaring them.
Further Problem Description
The issue can be HW or SW issue.
1. External power feed -- it was observed that in some occurrences, low VIN was observed.
2. Cisco PSU -- Faulty PSU.
3. SW -- rare concurrent access race condition.
