Yep the server and port are correct in the message. I also turned on the email notification and its the same in there. Whether virtualmin is actually using that is another question.
Like I said what’s weird is the same job (same settings) when run manually, works. Just not when scheduled.
It might be worth trying running tcpdump when the backup is running to see what port it is actually using. This may be a Virtualmin bug (using the wrong port), or it may be that the network / firewall is setup differently at the time the scheduled backup runs.
I did what you said Jamie - TCPDUMP set a schedule for timenow + 1 min watched tcpdump like a hawk - and the backup went through!
I was like WTF - then realised a few months back I’d had a lot of SSH attacks - so to counteract this I had setup an allow access schedule(the backup was outside that schedule to not affect my home bandwidth) for any IP - but didn’t exclude my webserver from the range of IPs
Just to confirm it was my fault and no fault of virtualmin!