When restoring a Virtual Server Backup to another server (eg backup server) the restore fails to account for the case where the home directory name (on Centos/RH: /home/homedirname) does not match the name of the user, instead only creating home directories using the username.
For example, I have home directories of the form: /home/websitename.co.uk, with usernames of the form websitename. (Where there is a name collision (.com/.co.uk) then I use a slightly different username, but these are very unusual cases, since for the most part .variations are only aliases.)
The result of the restore is that the home directory is set to /home/username, but all the configuration files (apache etc) still refer to the old pathnames, such as /home/websitename.co.uk
This means that restoration of a backup file to a backup server will not run without a number of manual changes. When several virtual servers have to be restored quickly in the event of a primary server failure, this will lead to extended downtime and troubleshooting.