My dad also used to self-host. Now I run all of the services he used to, and more.
Anyway, his server is still around so I thought I might as well use it for an offsite backup box, I run a matrix instance and nextcloud, as well as other things. But those two are the contents of which matter most.
How would you set this up?
Just a nightly rsync over sftp? That seems ineffecient. Is there a best way ro do this?
You can connect your main server and backup server to a VPS with wireguard. The main server backs up proxmox vms and cts to a proxmox backup server on the backup server. Nextcloud data can be backed up with something like duplicati encrypted over sftp to the backup server. Only hiccup about backing up Nextcloud is you should put it into maintenance mode first. You can write a script pre duplicati backup and post backup to enable and disable maintenance mode.
VPS is worth considering. I run no vms.
Duplicati seems like a good option.
Aware of maintenance mode. Thanks!