Symptom
After upgrading ACI, Fault F1451 seen on most Leaf Switches within APIC GUI. From the Leaf CLI issuing "show environment" may show some PSUs with "shut" status.
In NXOS, power supply will show as shutdown in show environment
Conditions
This issue is not specific to ACI or standalone NX-OS. It is an issue with the NXA-PAC-650W-PI or NXA-PAC-650W-PE, and it can occur in both NX-OS and ACI environments.
The issue is observed after a reload or upgrade.
Workaround
+ pull AC cable and re-seat the PSU
+ If re-seating the PSUs do not resolve this issue, try swapping the PSU with one from another Nexus
+ if swap does not resolve the issue, then RMA the defective/bad PSU units.
Further Problem Description
From affected leaf, you can confirm no power is being sent to board from the PSU with the command
leaf# vsh -c "debug eqpt internal psu dump" | egrep 'PSU.*:|0x97'
PSU2: N9K-PAC-650W
PSU2:
READ_PIN[0x97] = 0x000000e8 <---- all zeros indicates no power
