I have noticed at several customers with different ONTAP versions where ACP stops working on some modules. Installations that were at Full Connectivity, no changes made then when going back onsite at a future date to check systems or add shelves later, we often find "partial connectivity" and a module that has gone inactive.
In most cases, turning off and on acp fixes the issue. In some of the cases it does not and we have to pull and reseat the IOM module to get full connectivity back. ACP isn't required for a system but it isn't encouraging having to fix things that break without changes made.
I am seeing the exact same issue now as I was preparing for Data OnTap upgrade and checking the logs. I cannot find any good information on it either. Pulling the IOM and re-seating is odd and I bet when you go back it will be there again. I think I may open a ticket. If I find out anything I will pots back.
Alternate Control Path: Enabled
Ethernet Interface: e0a
ACP Status: Active
ACP IP Address: 192.168.0.129
ACP Domain: 192.168.0.129
ACP Netmask: 255.255.252.0
ACP Connectivity Status: Partial Connectivity
Shelf Module Reset Cnt IP Address FW Version Module Type Status
I checked my hosts and RC files for invalid entries; it looked good. I updated to the shelf firmware awhile back from 131 to 144. I got alerted from AutoSupport to update ACP this month so maybe the fix is in it. I have now updated the ACP firmware from 01.15 to 01.31. I will monitor this to see how it goes.