Basically what it says in the title: do you pull your backups a backup-manager host, or push them from each machine individually?
My initial inclination is to do it all from one machine, with one unprivileged user and a single cron file. That means, though, that there needs to be a remote user on each machine with g+r to everything, in order for ssh+rsync to do its thing.
Or, would it be simpler for each server to manage its own backups, probably as root, which means not having to change group permissions or identity?


both: pull for servers that are on 24/7. push for laptops (for example at login time, or other)
Same here.
Pulling doesn’t work if you don’t know when a system will be online, so it only makes sense for my laptop to push.