Arch Linux

Symlinking is a good way to have configuration files and associated data kept in a different storage area (on a backed-up RAID array in my case), or just safe in case of an OS reinstall being required. Putting all the important configuration files in one place makes sense from that perspective.

Most packages cope with their configuration files or directories being symlinks. However samba does not. If the /var/lib/samba directory is a symlink, the symlink gets deleted every time the package is updated and a stock configuration reinstated.

The package installer/upgrader should not arbitrarily delete stuff it doesn't recognise: it should either recognise a symlink and follow it, or not touch it and give a warning message. Thankfully it's only the symlink itself which is deleted, not the user database or configuration files.

Steps to recreate:
1. mv /var/lib/samba /var/lib/samba.real
2. ln -s /var/lib/samba.real /var/lib/samba
3. pacman -Syu (when samba needs to be upgraded).

Expected outcome: /var/lib/samba is still a symlink and any modifications required to files within that directory are done on the actual files within /var/lib/samba.real.
Actual outcome: /var/lib/samba is unlinked and replaced with a stock directory; no changes are made to /var/lib/samba.real and it is no longer used by samba (until someone goes in and fixes it). Effectively until someone goes in and re-links the directory, all your shares, users, passwords and other configuration data appear deleted.