Backup Exec 11d: No compression (at all) on new tapes

[itwasred]

Hi all,
I am running out of ideas here. We got Backup Exec 11d and Dell PowerVault 124T LTO3 tape libraries. We have a full backup running during the weekend and the job runs fine when I use older tapes (all of them were used before) it uses compression just fine but if I use new tapes (tried TDK or Sony) we get no compression at all and the job "fails" as the tapes do not have enough capacity.
We tried different brands, updated  Backup Exec 11d to the latest, updated the firmware of the drive and library, installed new drivers, even tried different barcodes. But we cannot figure out why the data on the older tapes get compressed and on brand new tapes not.
The backup job is always the same, we just use different tapes. Compression is set to Hardware, if not avail. then software.

Any ideas?

Thanks,
Andre

[Dev_T]

Hello,

Compression depends upon many things:
1  : What type of files we are backing up....Already compressed files wont be compressed further Example : .ZIP, .DLL..etc.
2  : Hardware compression is taken care by the Drive and software compression is taken care by the file system

Backup Exec do not compress anything....

Try to run a job using NTBackup with compression enabled and check.

Hope this helps...

[itwasred]

Hi,

these things should not really matter, as we use the same backup job - and of course do not modify any option - the only change are the tapes. With the old tapes everything is fine, with the new tapes the job fails as the tapes run out of capacity.

Here are some details from two old and two new tapes:

New tape #1:
General
Media label: 000503L3
Media type: LTO
Media set: DR Media set
Media location: DellDrive1
...
Appendable until: not appendable (Media full)

Statistics
Hours in use: 4.3
Data: 355 GB
Used capacity: 401 GB
Available capacity: 0 Bytes
Total capacity: 401 GB
Compression ratio:
Bytes written: 355 GB
Bytes read: 192 KB
Mounts: 2
Seeks: 15

Errors
Seek Errors: 0
Soft write errors: 152854
Hard write errors: 0
Soft read errors: 0
Hard read errorsS: 0


New tape #2:
General
Media label: 000504L3
Media type: LTO
Media set: DR Media set
Media location: DellDrive1
...
Appendable until: not appendable (Media full)

Statistics
Hours in use: 3.4
Data: 296 GB
Used capacity: 401 GB
Available space 0 Bytes
Total capacity: 401 GB
Compression ratio:
Bytes written: 296 GB
Bytes read: 192 KB
Mounts: 2
Seeks: 15

Errors
Seek Errors: 0
Soft write errors: 138505
Hard write errors: 0
Soft read errors: 0
Hard read errorsS: 0


OLD tape #1:
General
Media label: 000464L3
Media type: LTO
Media set: DR Media set
Media location: DellDrive1
...
Appendable until: not appendable (Media full)

Statistics
Hours in use: 165.4
Data: 555 GB
Used capacity: 401 GB
Available space 0 Bytes
Total capacity: 401 GB
Compression ratio: 1.39:1
Bytes written: 6.25 TB
Bytes read: 6.23 TB
Mounts: 47
Seeks: 663

Errors
Seek Errors: 0
Soft write errors: 203446
Hard write errors: 0
Soft read errors: 147
Hard read errorsS: 0



OLD tape #2:
General
Media label: 000465L3
Media type: LTO
Media set: DR Media set
Media location: DellDrive1
...
Appendable until: not appendable (Media full)

Statistics
Hours in use: 147.3
Data: 592 GB
Used capacity: 401 GB
Available space 0 Bytes
Total capacity: 401 GB
Compression ratio: 1.48:1
Bytes written: 7.24 TB
Bytes read: 7.23 TB
Mounts: 44
Seeks: 447

Errors
Seek Errors: 0
Soft write errors: 147398
Hard write errors: 0
Soft read errors: 96
Hard read errorsS: 0


Thanks,
Andre

[gswell]

New tapes have no compression and old tape have an avg of 2:1 compression. 

Nothing changed but the tapes and now I need two tapes to complete a backup.