I'm in the middle of implementing a (very) custom offsite backup solution for two of my clients. I am currently backing up their servers to my local storage servers here at my location. It's part of a bigger strategy.
However, there is quite a bit of data (more than 1TB) involved and pushing all of that over the 'Net just wasn't going to cut it. So I physically drove to both locations and rsynced their machines to a large portable eSATA.
Now, all of their data has been placed on the storage servers where the backups are going to end up. I've rsynced their servers with the local storage servers as well just to ensure I have the most up to date copies of all of their files. For all intents and purposes I have mirror copies of their servers on mine.
Here's my question (finally): The backup solution is going to use rdiff-backup, and I'm wondering how it will behave when I invoke it.
--> If the copies of the files on both ends are identical, will rdiff-backup have to push all the data again, or will is just do a quicker comparison like rsync's algorithm does? I know the initial rdiff-backup backup has to complete in order to get the incrementals rolling. It's the initial backup I'm concerned about.
I know this is the rsync zone, but I couldn't find one about rdiff-backup (or much of anything other than commercial software...). I tried a few tests but they came up inconclusive since I can't actually "see" what rsync-backup is doing in the background.