DLT7000 Backup Compression - How much will it compress?
Posted on 2004-12-01
i have an external DLT7000 (35GB uncompressed/70GB compressed) backup drive, connected via SCSI to a pc running Windows 2000 Server.
i can select files and folders to backup and just before it backs them up it has a look to see how many GBs of data there is (uncompressed). it then starts the backup with hardware compression. i want it to look at the files i have selected for it to backup, and work out the compression of the particular files and tell me how much data it will be with compression.
for example, if i select a folder which has 40GB of data in it. i know this folder won't fit uncompressed on a DLT tape (35GB) so i turn on hardware compression. the compression depends on the type of files being backed up, some files can't be compressed, others can, so i have no way of knowing if that 40GB of data is going to fit on the tape or not. it may be able to fit it all on even with some space available, or may not be able to compress it at all.
is there a way or an application that can tell me before the backup job starts if it's going to fit on one tape or how many tapes i need?
i hope i have explained this well enough, feel free to query if not.
any help appreciated.