samba preexec and postexec to the rescue ...

I had yesterday to migrate a server running CentOS 4.x to a new xen domU running CentOS 5.4 . While the migration was the easy part (including the data), the 'problem' I had was the backup part. In fact the backup application used is a proprietary one (Computer Associates Arcserve, to keep it 'secret' .. ). Well, that proprietary backup agent (v11.5, old but still used 'here') doesn't work on CentOS 5.4 (glibc issue) and i didn't want to find a workaround that problem (with LD_LIBRARY_PATH or some other tweak). That's where Samba came to the rescue : the Arcserve backup server can backup Windows nodes (and so Samba nodes too) through UNC path. OK, but for the previous system i had prebackup and postbackup jobs/scripts on the CentOS node (doing specific things, including creating a lvm snapshot and removing it after the backup job). How could i do that now through the samba-backup-method approach ?. Well a standard cron job on the CentOS machine was of course always doable but I (we ?) prefered some kind of 'triggering action'. That's where i used for the first time the preexec and postexec options for a samba share. Basically it still uses my prebackup and postbackup scripts (doing the snapshot and mount it, as well as the reverse , obviously) and expose that mounted snapshot during backup time for the backup server. .. Working nicely and maybe it can give you some ideas .... ;-)