I am using rsync for backups from remote FTP to local computer.
I read on internet that rsnapshot is better.
Just want to know which is used in production environment
rsnapshot uses rsync and
cp -al to keep an historical archive with minimal extra storage. in short:
each copy 'seems' to be a full complete copy, but in fact any unchanged file is stored only once. it appears on several directories using hard links.
the process is simple, let's say there are currently 4 copies, back-0 through back-3. when rsnapshot is invoked, it:
rm -r back-3)
mv back-2 back-3)
mv back-1 back-2)
cp -al back-0 back-1) this creates the back-1 directory but insteado of copying each file from back-0 to back-1, it creates a hardlink; in effect, a second reference to the same file. this second name is just as valid as the first one, and the file's data won't be removed from the disk until both names are deleted.
once you get familiar with the procedure, you'll find it very handy. it's not complex at all, sometimes i do it manually to keep sporadic 'previous versions' at interesting points of time (just before an important upgrade, just after installing and configuring a system, etc)
A late answer on this FAQ: rsync is a copy/sync tool, very efficient for distant backups. rsnapshot and rdiff do more than a single backup: they keep a history of the backup. AFAIK, rdiff does it by keeping diffs of the files between each backup (differential backup), so the archives are not accessible as-is. OTOH rsnapshot uses hardlinks for identical files full copies of every changed files, so the archives are plain directories that users/admins can search from. So there are cases where each performs best.
We use rsync to replicate data across the WAN from our primary backup server to our warm sites backup server. It has worked very well for that purpose. As far as rsnapshot I am not familiar with what the advantages would be for using that solution.