root@raspberrypi:/etc/.pihole# git fetch origin
error: unable to resolve reference refs/tags/V2.9.2: Invalid argument
From GitHub - pi-hole/pi-hole: A black hole for Internet advertisements
! [new tag] V2.9.2 -> V2.9.2 (unable to update local ref)
error: unable to resolve reference refs/tags/v2.1: Invalid argument
! [new tag] v2.1 -> v2.1 (unable to update local ref)
WELL DONE GUYS!!! I am so happy that i decided to make pihole my primary DNS in my network...
Something bad happened to your repo, we have seen this before and chances are high that this is related to write errors on pulling power from the Raspberry while there is some I/O pending (which sometimes just hangs around and never seems to finish for some unknown reason).
It will be best for you to start over and clone the repos again. Your settings will be preserved
I've deleted .pihole and used the curl script with update option selected. This worked. Calling pihole -up afterwards results in the message all is up to date.
Okay, that essentially did the same for the .pihole repository. Wans't sure if it maybe also affected your adminLTE repo, but glad that is working for you now!