
*** Uplink FRU module hardware authentication failed. ***
and
%PLATFORM_PM-6-FRULINK_UNKNOWN_INSERTED: Unsupported FRU module inserted in slot 1
When we ran “show inventory” the module was not listed. We then downgraded back to the old version and we received the same messages! We had a few other identical network modules, so we swapped them but the problem persisted. A module that ultimately worked was the C9300-NM-8X which is a 9300 switch module, but it appears identical to the C3850-NM-8-10G. I have ordered more of these to keep as spares in case this happens again!
The following Cisco bug seems to line up with my experience: https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvd86925/ Even though the bug claims the problem is fixed in 16.3.X and above, however I can confirm this is not the case.