Recently I observed that our 2 machine ArcGIS Server Site 10.6 restarts its AGS Instances (Not machines, just the windows AGS Service) at a random moment i cannot determine. After reading through logs i can find following statements just before the shutdown begins:
"Server license version does not match effective current version."
I cannot tell if this is a red herring or actual cause of the problem? After the restart AGS runs normally till the situation repeats. Load does not seem to be the factor - even if the box sits idle this keeps happening.
Our software is fully licensed so there should be no issues with this. The machine has plenty of free RAM left. CPU is not busy, at 10% ish. But now and then one of the Instances suddenly undergoes a full initialisation.