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Backupexec 2010 R3 Compression

Created: 26 Dec 2011 | 15 comments


I am using BackupExec 2010 R3 and when I am tring to write on LTO4 taps the compression was working before and after while the compression is no more running. That makes the taps full faster and the backup that was take 2 taps by compression it is now take 4 taps

Can you please help me in this case?

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Sush...'s picture

Ideally Backup Exec does not perform any compression but it just send the command to the hardware device to perform the compression.

Refer to the following technotes to ensure that Backup Exec is able to send the compression command to the hardware. : How to perform a test to verify compression : How Backup Exec for Windows Servers controls hardware compression on tape devices.



Hope this piece of Information Helps you... and if it does then mark this response as Solution....!!!'s picture

Thanks Sush for your help

This utility gives Hardware compression for one tape and the other tape doesn't has hardware compression I don't know why???

Striker 303's picture

Have you tested this article, as given by Sush:

If you can see "Setting compression on"  and "Compression is configurable" in SGMOn.
time to contact Hardware manufacture.

Hardware based compression is provided by Actual hardware itself, Be only sends
SCSI commands to initate it.. so if BE is sending commands hardware is at the fault end.
some time specific media goes bad however in your case you have mentioned..issue with all tapes.

Striker 303's picture

Check backups job properties and make sure "hardware based compression" is still selected.'s picture

This option is selected and the string thing that it was making compression before and some times on some media not other

pkh's picture

1) check your joblog to see that compression is turned on, be it hardware or software.

2) check that you are not using software encryption with hardware compression.

3) check that you are not compressing data which is already compressed like zipped files, movies and picture files.  If you are, you could end up with something bigger than the original.  See my article on this subject.'s picture

The encryption is off

I am using Harware compression if avilable and if not software

I am not compressing data it is files that can be compressed like : images,execl,pdf,doc,....

pkh's picture

Check that your hardware compression is turned on.'s picture

The enable compression check box is set and the block size is set to 64K

ArulPrasad's picture

Check the Media used By the Job. Check the statistics information and see what is the Ratio of compression From the Media set Tab.

If the media is Being Used extensively or if the Tape drive header is Dirty there is a chance tape space dimishes.

Arul's picture

The ration is 1:1 for almost all and it doing that for fresh media also

CraigV's picture your drive manufacturer's diagnostic utility and erase the tapes using this. Once done, run the backup again through BE and see what you're getting.

Alternative ways to access Backup Exec Technical Support:

pkh's picture

You got to expand your joblogs, look at each of the resources that you are backing up and check what is the compresion ratio you are getting for each one.  This way you can narrow down to which resource is not compressing and then go on from there.'s picture

There is a milions of files and it is to hard to trace that. The string thing that all thoes files was compressed before until certain time and now it doesn't

JvdPoel's picture

We had a similar problem some time ago with a Sony Tapelibrary.

Running the Sony Tapetool and sending the results to Sony it appeared we had a high rewrite rate.
This means the tapedrive needs to rewrite the same data several times before it is OK, this caused that our tapes were only used for half of their capacity.  They replaced our tapelibrary and problem solved.

I suggest you focus on your tape device, do diagnostic testing and contact the manufacturer.