error 503 everynight

[LucillaV]

I have a server with opensuse 13.1 plesk 12.0.18 update #68 at 8 october
Since 1 week every night around at 22.30 the sites give "error 503 service temporarily unavailable". Other services (ftp, plesk, ssh) work, only the web no works
I need login to plesk and reread the IP (tools & setting -> IP addresses) and the sites go on.
I don't know what problem is. nothing in cron, nothing in log... what I can check?
Now the Reserve Proxy Server is stopped, but the error comes both with nginx enabled or nginx disabled
Any suggestion?

 

[vlikhtanskiy]

Hi @LucillaV!

Maybe there are some scheduled backups with enabled suspend during backup?

 

[LucillaV]

No, any backup. No backup scheduled in plesk and no backup outside. It is a VM and the backup of all VM starts after midnight