Hello everybody,
since a couple of years now, I am backing up my 2008 R2 Server (DC and fileserver) with Microsoft Windows Server backup. For this task I am using five external USB HDDs (2TB). My server contains a 120 GB system drive and a 2 TB volume for storing data of
our fileserver as well as different backups from other servers. My data drive is relatively full. I have about 900 GB of data stored, 800 GB free. So on my 2TB destination drives, the first full backup only uses about 1,2 TB of space. The rest, 800 GB, should
be availavble for the smaller incremental backups (I know it's not a real incremental backup because of VSS, but WSB also calls it incremental)
I am backing up daily and this worked perfectly fine for years. I always had about 50 to 80 backups available because the daily rate of change was always relatively small. The first time WSB backs up all the data, and the following ones, it only copied a very small ammount (the changed data), which was maybe 5 or 6 GB at most. This is also the maximum amount of data changed per day. The fileserver with userdata changes at most 1GB, the rest are smaller backups, coming from other servers.
Since some time now, I have a problem with this. Windows Server Backup copies too much data per day. Sometimes "only" 30GB but some times also 60GB or 90 GB. This can never be the ammount of changed data. Because of that, the 2TB destination drive can only store about 5-8 backups, instead of much more as before.
Because I can not see, which files are really copied, I can't find where the problem is. I first thought it has something to do with our DFSR fileserver. But WSB does not back up the staging, conflicts and dfsrprivate folders by default (registry key "FilesNotToBackup").
I did a simple file based search in the explorer, searching for files which changed the last day. The results are as expected only about 3 GB big.
I already deleted my backup schedule completely, recreated it from scratch and also formatted all my drives in this step, so it is totally clean. But I have the same problem. The last 4 days, I had the same destination drive connected. First day, full backup all data, next day 40gb, next day 99gb.
I do not know what I can do.