SBS 2003 Backup smaller than normal (4-6GB)
Posted on 2006-05-06
We are about to do a restoration on an existing server to a new server configured the exact same way. This was recommended by the documentation for using the backup restoration features to restore the entire server. The current server was damaged in an act of vandalism, and the insurance company want's to be sure that the server is not comprimised, so we are replacing it with an exact replacement of the same server.
We decided on this weekend to do the conversion. Our issue is that when we ran our backup after getting everyone out and turning off exchange so no new mail could come in, is that the size of the backup file is quite a bit smaller than normal.
We use shadow copy and verify since the manufacturing plant that utilizes this server runs 3 shifts. The normal backup file size is 35GB and today when we ran the backup the size was only 26GB. Now, if I take the size of the physical drives and subtract the free space I come up with somewhere around 30GB. The drives are about 35GB total with about 5GB free space. I'm trying to figure out where the discrepency in size is.
The differences between a normal backup run and this one is that we shut down email last night at 9pm, so no one is in that. No one is logged in, and of course, no files are open, which normall never happens during backup time.
The only idea I can come up with is that since the server is usually under a good amount of use during backup that the extra size created could be uncompressed or system state files or both. My question is: Could that cause the size to go up so drastically....from 26GB to 35GB for the backup file?
For testing, we have run three backups since shutting everything down, and they are all around 26GB, so it seems that this number is correct. I cannot figure out why it is usually 35GB though. We plan to finish this tonight, please respond ASAP.