rsync and symbolic links

some possible behaviours of rsync (from the man page):

(1) SKIP:

default case => symlinks are simply not followed

(2) COPY THE LINK:

"symlinks are recreated with the same target on the destination"

rsync --links

also: rsync --archive implies --links

(3) FOLLOW THE LINK

rsync --copy-links

safe/unsafe:

relevant for case 3 is the "safe" vs. "unsafe" difference which I did not understand good.

This is what is written: "An example where this might be used is a web site mirror that wishes ensure the rsync module they copy does not include symbolic links to /etc/passwd in the public section of the site. Using --copy-unsafe-links will cause any links to be copied as the file they point to on the destination. Using --safe-links will cause unsafe links to be ommitted altogether."

Always back up on a dedicated partition or disk!

My home dir on a certain server was backed up by another company. I set under my home a soft link to another location (several Gb of data). What I didn't know: their backup script was rync-based *with* the option --copy-unsafe-links. Rsync followed the link and backed up tons of stuff clugging the backup hard disk. They used the same hard disk and the same partition also for another function: email server. So that softlink disrupted the email server! At first I though I was to be blamed, but after a second thought, I understood, that it's not 100% true: they should have *never* run the mail server on the same partition where they backed up that stuff!