Tape Capacity

[jared_chainey]

Our tapes are AIT3 tapes and should have a capacity of 100GB. Backup exec reports them as having a capacity of 35GB. Is this correct?

We can get 135GB on them using hardware compression although it reports the compression ratio at over 3:1

I cannot find anywhere to specify that the tapes are AIT3 with a capacity of 100GB.

Any ideas?

[Ken_Putnam]

What kind of tape drive do you have?

What is it's rated capacity?

[jared_chainey]

Its a Sony SDX-700c. 100-260GB apparently

[Ken_Putnam]

If you are using Hardware compression, where are you finding a report on compression ratio?

If you are gettng 135GB on a 100GB tape you are getting about 1.35:1 compression, which is pretty close to what I use a a rule of thumb, until a specific server and it's data has been backed up a few times.

[jared_chainey]

I am using the compression ratio that is displayed on the media properties for the tape in the media section. Is this hardware or software compression? Can I tell somehow whether a job has used hw or sw? All my jobs are set to use 'hardware if available otherwise software'

Thx

[Ken_Putnam]

each job step should tell you whether the job is using compression and whether it is SW or HW.

[jared_chainey]

Thanks... sorry, what do you mean by 'job step'?

The job logs do not mention the compression ratio anywhere.

[Ken_Putnam]

If you backup more than one share in a job, each share on each server is a "job step" and reports start/stop times total bytes backed up and whether compression has been used

If you don't see anything about compression in the job log, verify that compression has been selected in the job description.

if yoy have hardware selected,
1) Try shanging to software
2) From Devices, right click the drive\Properties, verify that "Enable Hardware Compression" is enabled.

[jared_chainey]

Blimey, this veritas is not very user friendly.

If I highlight 'stand alone drives' (I only have one) then the pane that appears with the heading 'drive properties for compaq 1' says that 'Enable Hardware Compression' is 'No'.

If I right click on Compaq 1 below standalone drives and select 'properties' and then highlight configuration, the box saying 'enable compression is ticked.

Confused - I am.

[Chaitanya_Khurj]

Do install Service Pack 1 if you haven't done so.

VERITAS Backup Exec (tm) 9.0 for Windows Servers revision 4454 - Service Pack 1
http://support.veritas.com/docs/267151

Also, have you checked if the device supports reading of available capacity or total capacity ? Is this supported ? Also could you please let us know drive name and the company name to which they belong ?

NOTE : If we do not receive your intimation within two business days, this post would be "assumed answered" and archived.

[Chaitanya_Khurj]

Also, install this Hotfix,

VERITAS Backup Exec (tm) 9.0 revision 4454 Hotfix 2 - Device and Media Support (adds support for the Super Advanced Intelligent Tape media type)

http://support.veritas.com/docs/267153

Install SP1 first and then Hotfix 2, reinstall the latest device drivers.

VERITAS Backup Exec (tm) 9.0 - Device Driver Installer (20040115) - Includes Tape Driver Release (20031222) and Robotic Library Release (41) (Intel Only)

http://support.veritas.com/docs/265139

NOTE : If we do not receive your intimation within two business days, this post would be "assumed answered" and archived.

[Madhuri_Shenoy]

As per our previous reply, marking the case as "assumed answered" and moving it to "answered questions" pool.