Does Rsnapshot work on the Fat32 filesystem?
So I'm not sure what to think.
rsnapshot is just making use of
rsync so it should work fine with backing up a variety of files from file systems such as ext3, ext4, FAT, and NTFS.
The comment that you're referring to:
Backing up to external usb HDD's works perfectly, but one needs to use a ext3 or similar formatted drive that supports hard links. So no FAT32 or NTFS drives.
Is only saying that you have to use a file system such as ext3 or ext4 as the file system that you're backing up to.
This comment has to do with the mechanism that
rsnapshot enlists to make it's backups.
Rsnapshot similar to another tool,
rdiff-backup, is saving disk space by creating links to files within a given backup vs. actually making a physical copy of the same file day in and day out.
Say we have this directory being backed up:
$ tree somedir somedir |-- afile1 |-- afile2 |-- afile3 `-- afile4
Day1's backup would include all the contents of somedir.
Now let's say we only changed file afile4 during Day1, so in Day2's backup, we'd have links to files afile1 - afile3 and a new copy of afile4.
Rsnapshot is creating links in the file system from backup set to backup set for files/directories that haven't changed from the prior day.
In order to make these links, you need to have a file system that supports feature, which the FAT/FAT32 file systems common on a lot of external USB drives, doesn't.