goosegrapes
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Can't backup more than 200GB on LTO-2 tape with Brightstore Arcserve
Since a while now every daily full backup writes data until it reaches approx. 202 GB and than it asks for a new tape. We use LTO-2 tapes and the Dell PowerVault 114T. The appropriate servcie in server 2003 was stopped and set to manual (removable storage) and the windows device drivers disabled. The second backup (two tape drive) works flawless with approx. data of 140GB. The error message displayed is W3828. Unable to find this or a blank media.
The tapes are new, and the tape drive as well. I formated a test tape but no change. The compression is turned on in Arcserve.
Any input is very much appreciated.
The tapes are new, and the tape drive as well. I formated a test tape but no change. The compression is turned on in Arcserve.
Any input is very much appreciated.
TapeDude
How compressible is the data? LTO 2 tapes have a native capacity of 200GB, so if you're trying to back up something that is already highly compressed - say, AVIs, JPEGs, zip files - you won't get any more than native capacity.
First off, have you been able to get more than 200gb on these tapes and drives before?
are you sure you haven't reached the max capacity of the tape and drives? While the tape allows for 200gb native/ 400 compressed, it may not be able to reach that cap with the current drives installed. It also may be a problem with the data being compressed. the amount of compression capable depends how compressible the data is. Sometimes you can reach 4:1 ratio, sometimes 1:1 is the max you can get.
are you sure you haven't reached the max capacity of the tape and drives? While the tape allows for 200gb native/ 400 compressed, it may not be able to reach that cap with the current drives installed. It also may be a problem with the data being compressed. the amount of compression capable depends how compressible the data is. Sometimes you can reach 4:1 ratio, sometimes 1:1 is the max you can get.
ASKER
Thanks for the commends.
I had successful backups before. They were in the area of 250GB. A lots of the files backed up are .tif, jpeg and autocad drawings. Is there an option were I can find the actual compress ratio?
I had successful backups before. They were in the area of 250GB. A lots of the files backed up are .tif, jpeg and autocad drawings. Is there an option were I can find the actual compress ratio?
BE displays the compression ratio in the MEDIA tab. Click on the MEDIA tab and select one of your media sets. It will then show the tapes in your media sets and the information related to it. Compression ratio should be one of the columns listed. If it isnt there click on the column and add it in.
Note: this indicates the compression ratio already applie to it. it does not indicate the maximum capability of compression.
If you are backing up a lot of files as listed above then do not plan on getting much out of it. It is best practice to plan your backups around the native capacity of the tape, unless you've tested the backups extensively and know for a fact it will always hold enough in a compressed state.
Note: this indicates the compression ratio already applie to it. it does not indicate the maximum capability of compression.
If you are backing up a lot of files as listed above then do not plan on getting much out of it. It is best practice to plan your backups around the native capacity of the tape, unless you've tested the backups extensively and know for a fact it will always hold enough in a compressed state.
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If you want to know how compressible your data is, you could try compressing a representative sample using winzip or 7zip. If you're only getting a few % decrease in size, then you know why you're not squeezing much more than the native capacity onto the tape.