We have a clustered VIDM installation which gave us login problems after a SDDC manager upgrade from 4.4.1 to 4.5.1, this does not seem related at all but the timing is when the problems started.
After some investigation we noticed we could not login to the second node with root or sshuser and noticed that the diskspace was full.
To solve this we needed to reboot the node and go into single user mode to reset the root password, while doing that we also found a 16GB old messages file. We removed the file and reset the root password and rebooted the node. Use this article if you have never done a root password reset before on a vmware photon appliance. Since we have it connected so VRSLCM we also ran a remediate because it still showed critical, after the remediate was finished it turned to green.
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