Video Screencast Help
Search Video Help Close Back
to help
New in the Rewards Catalog: Vouchers for "Symantec Technical Specialist" and "Symantec Certified Specialist" exams.

B2T runs at 6 MEGAbytes per minute

Updated: 01 Oct 2010 | 8 comments
William Wagers's picture
0 0 Votes
Login to vote

We just replaced our old Ultrium 1 8-tape autochanger with a brand new Ultrium 3 8-tape autochanger.  I installed the hardware yesterday, and had a very easy and quick installation using HP's Library and Tape Tools.  I went in to BE 12.5 and converted our Backup2Tape jobs to go to the new drive; it accepted that with no problem.  When I ran a test backup yesterday, I got a throughput of 6-12 mbps.  I thought that distressing, since our Ultrium 1 drive got about 300-400 mbps, and the blurb on this drive said it should get in the gigabyte range...  On the offchance that our standalone Ultrium 3 drive was conflicting, I removed it and put it on another server.  I still get very slow speeds.  I have restarted the server, reseated the SCSI cables, restarted the autochanger, removed the drive in both BE and L&TT and re-added it...


Did I miss a setting somewhere?  Does anyone have any advice?

 

Thanks,

William

Comments

Ken Putnam's picture
16
Mar
2010
1 Vote +1
Login to vote

Have you run the diagnostics

Have you run the diagnostics through LTT against the drive?

From the Devices Tab, right click the drive\Properties

What are the settings for Block Size, Buffer Size and number of Buffers?  Also the settings for both Single Block options?

If this response answers your concern, please mark it as a "solution"

JoaoMatos's picture
16
Mar
2010
0 Votes 0
Login to vote

Hi William, i do not

Hi William,

i do not understand what you me  "On the offchance that our standalone Ultrium 3 drive was conflicting"?, this does not sounds good to me.

How is autochanger connect to the server?

Is you autichanger an HCL device?

I think your autochanger have a SCSI terminator, remove and reconnect SCISI terminator again.

Is the terminator light on?

Another test you can do, I do not know what hardware we are talking about, change places of terminator and SCSI cable.

Did you reistall Symantec Tape drives?

Regards,

JoaoMatos

 

Regards,

JoaoMatos

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

William Wagers's picture
16
Mar
2010
0 Votes 0
Login to vote

Re: Have you run the diagnostics

All settings are default. Block Size and Buffer Size are set to 64KB, Buffer count to 10, and High Water count to 0. Both read options are set to unchecked, and both write options are set to checked.

 

So when I ran the diagnostics, I found an error stating that I was getting a high polling rate on my tape drive.  I found these two links from a google search:

http://support.microsoft.com/kb/842411 

and

http://h20000.www2.hp.com/bizsupport/TechSupport/D...


....and after following the advice in those links, I am still sitting at 22.00MB/min.  I guess that's better than 5.00, though.

Ken Putnam's picture
16
Mar
2010
0 Votes 0
Login to vote

Disable both Single Block

Disable both Single Block options, as this disables buffering

BackupExec will read one block of data from the source, write it to the target, read another single block etc 

Shouldn't make a huge difference, but if you have sufficient RAM you also could up the buffer size to 128K or 256K

If this response answers your concern, please mark it as a "solution"

pkh's picture
16
Mar
2010
0 Votes 0
Login to vote

@Ken, What about the blksize?

@Ken, What about the blksize? Would setting it to higher than the default blksize of 64k speed things up?

William Wagers's picture
16
Mar
2010
0 Votes 0
Login to vote

Re: Have you run the diagnostics

Check that... It's dropped back down to 6.00. :-(

CraigV's picture
16
Mar
2010
0 Votes 0
Login to vote

Hi there, We have had a

Hi there,

We have had a problem with high polling rates, but this was specific to a SAN-attached HP tape library, not SCSI.
What I normally do when replacing a drive is to install the Symantec drivers again through BEWS. Once done, restart the services, and then check that the drivers are correctly installed through Device Manager (should show Symantec).
What you can also do is make sure that the RSM service is stopped and disabled.
Failing that, Ken is quite correct in pointing you to the diagnostic options in HP LTT...you need to run those tests and check throughput, and whether or not there is a problem.
unless this is a brand-new unit, if it is a replacement, it is possibly reconditioned (trust me, I have had a reconditioned unit delivered, as well as a brand new unit arrive DoA!), and you need to eliminate hardware faults.

Laters!

If you find this is a solution, please mark it as such.

CraigV's picture
29
Mar
2010
0 Votes 0
Login to vote

Have you come right here...?

Have you come right here...?

If you find this is a solution, please mark it as such.