I'm trying to check if the System State of my servers in a multiserver setup (with ISPConfig 3 on Debian) is still functional. Is there some way to test this or to force a manual renewal/update of the System State of a single server or the whole multiserver setup?
There is no way to test this manually, but you can choose one specific server under 'Server to monitor' and then check the uptime under 'Server load'. If this is the same as what you see when running the uptime command on the server, the connection is working.
Uptime is updated every 5 minutes, so if it stays the same for more than 5 minutes, then the connection does not work.