I've got quite a few machines with quite a few directories that I want to keep in sync. For example, I have
/var/backups on some servers that I want to take a copy of on a nightly basis. rsync is a tool I've been used so far, and initially sounds like a natural choice, because I need the following;
- Synchronization of directories over WAN connections (eg, home server to sync with public web server)
- Easily available in repositories for most Linux distributions (big bonus, makes updating easy)
- Incremental transfers
- Works without any additional ports (just SSH/22) open
I'm running rsync as a standard cronjob at the moment. However, these are the limitations I'm trying to address with a recommendation;
- If /var/backups (or wherever I'm copying from) is empty, or if a file cannot be copied due to permissions, I get no warning or notification.
- For large directory sync's (eg, 3-4 Tb), it's difficult to see the status of that sync at a glance.