Veritas Backup Speed - is it normal

[Antoine_Khater]

I have veritas backup exec 10 installed on a server and I am taking backup from various servers in my LAN (over the network) veritas is connected to a Compaq MSL5000 series tape library, the backup speed I am getting is of only 108 MB/Min is it normal? should I be at a MUCH higher rate?
Drive properties 512 512 10

thanks

[priya_khire]

Hello,

The throuput rate does not seems to be normal. There could be several causes for this. Refer to the following technote:

Reasons why the data throughput rate can be slower than the theoretical maximum when backing up to tape media

http://support.veritas.com/docs/231488

Also try a job on a backup to disk folder and check the throuput.

Note : If we do not receive your reply within two business days, this post would be marked �assumed answered� and would be moved to �answered questions� pool.

Regards.

[Peter_Ludwig]

I do have the same libraries with SDLT2 drives and with 64k/64k/10 I'll get some 1300 MB/min with 'normal' office data (maybe 1:1.3 compressible).
(Over Gbit LAN, maybe there could even be a little bit optimized, but as it is no problem now.

greetings
Peter

[Scott_Hammonds]

I also am having backup speed issues. I think the problem may be related to compression on my Exabyte EZ17 robotic tape library. The compression of the tapes is listed at approximately 35:1 and my job rate is only about 87 MB/min. Also, when I do a full backup, the job uses multiple tapes even when the tapes are not full. Is there anyway I can force the backup to be done on one tape rather than it asking for overwritable media even though the tape isn't full?

[Ken_Putnam]

BackupExec will always use all of a tape, once it starts writing to it. If you are getting less than the native (uncompressed) amount of data on a tape, either your jobs are APPEND not OVERWRITE or there are problems with either the tape drive or the driver

Be aware that you will probably NEVER see the max compression quoted by the drive manufacturer. I use about 1.3:1 as a rule of thumb until a given share has been backed up a few times and I can start averaging them.

[Russ_Perry]

If the throughput is being held down around 100 MPM with a high performance tape drive, often the scsi controller driver is the cuprit. Update it with the latest version. Also, the 512/512 are not standard settings for that tape drive in Backup Exec. Does the throughput stay low when you go back to the default settings which are probably 64/64?

Russ

[Antoine_Khater]

Hi, and thanks for the reply.

Sorry for not answering this before, but I thought I'll get email notification if my thread gets any replies.

I did try to do a disk backup and the througput I got was in the 1200 range more than 10 times faster :(

[Antoine_Khater]

> If the throughput is being held down around 100 MPM
> with a high performance tape drive, often the scsi
> controller driver is the cuprit. Update it with the
> latest version. Also, the 512/512 are not standard
> settings for that tape drive in Backup Exec. Does the
> throughput stay low when you go back to the default
> settings which are probably 64/64?
>
> Russ

Thanks for the tip, I did reset those values to the default 64/64/10 with no change of speed at all...

My library is directly connected to a SAN so in this case it can't be the SCSI adapter any other hint

[Antoine_Khater]

> I do have the same libraries with SDLT2 drives and
> with 64k/64k/10 I'll get some 1300 MB/min with
> 'normal' office data (maybe 1:1.3 compressible).
> (Over Gbit LAN, maybe there could even be a little
> bit optimized, but as it is no problem now.
>
> greetings
> Peter

Hi and thanks for answering my thread, can I ask you some questions since you have the same library
1) is it connected to a SAN like mine or directly to the server
2) What firmware version are you running

thanks

[Peter_Ludwig]

My libraries are directlky connected to a server and I do have firmware versions 5.07 on both of them. As I do not have any troubles I did not update it lately.

But IMHO the drives' firmware versions are more interesting, these have version 5555 (SDLT 2)


greetings
Peter

[Antoine_Khater]

> My libraries are directlky connected to a server and
> I do have firmware versions 5.07 on both of them. As
> I do not have any troubles I did not update it
> lately.
>
> But IMHO the drives' firmware versions are more
> interesting, these have version 5555 (SDLT 2)
>
>
> greetings
> Peter


I'm not quite sure what solved the problem, but Peter sure did help what I did was

1) Set the drive properties to 64/64/10
2) firmware upgrade and driver upgrade

and now i am having rates of peaking at 1200 1200 mb/min with an average of 933 mb/min

thanks