I have a layout of 2 ldap, 2 mailbox, 2 mta. I'm looking at getting my backups organized a bit better and I noticed something strange. First the documentation is a bit out of date or incomplete because where it describes the layout of the backup structure it indicates that there should be a ldap directory in each session but when you break up ldap and mailboxes on separate machines, naturally the mailbox backups don't contain a ldap directory and the ldap server backups only contain a ldap directory. No big deal.
The thing that confuses me is that the mailbox servers have a default of 1 weekly full and 6 incremental backups, but the ldap server seems to only have the fulls scheduled. Does it make sense for the ldap server to have incremental backups done and if not, why not. Where do changes between fulls get saved between fulls? Are they somehow part of the mailbox backups?