In this document we want to comment some architectural and software choices.
Every server that we've installed has RAID 1 o 5, hardware o software. What type of RAID to choose is up to you. The only hardware RAID controller that we can reccomend is 3ware as it supported by smartmontools and gives the possibility to access S.M.A.R.T. information and has an excelent daemon which will drop an E-mail in case of some problems. In all other situation we use software RAID. Server controls 2 parameters - temperature and the quantity of reallocated sectors which gives us the possiblity to prevent problems which leads to data loss. Integrity of software RAID is also under control.
LBS uses XFS. XFS has such excelent utilities as xfsdump (and xfsrestore) which gives us the possibility to make hot backups and hot copies and xfs_growfs which gives us possibility to add disks in case of hardware RAID 5. We don't recommend to use LVS as it complicates data recovery in critical situations.
The central part of LBS is OpenLDAP. Samba and Qmail uses it to store domains and users information. Labe also use OpenLDAP. To access OpenLDAP should be used tools apropriate for every program. To access OpenLDAP directly can be used phpLDAPadmin which you can find in the Expert Zone section of web interface. This is very usefull when something is wrong with Samba o Qmail. This is "raw" access to LDAP so it should be used with caution.
Hylafax configured not to use any type of user authentication which seems to be an overkill for a small organization.