Slow remote backup since April MS updates?

[Jason_Dean]

Hi

Running v10.0 SP1 on a Windows 2003 server with AIT drive. Backup of local machine is working fine.

Backup job includes a remote Windows 2003 server which was fine until a couple of weeks ago - now very slow backup throughput.

The only thing I can think of that changed is the April MS security updates, including KB911562 and KB908531. Are there any known issues with Veritas?

Thanks!

[priya_khire]

Hello,

No there are no such known issues. Slow backups can occur due to varied reasons. Refer to the following technotes for more information on them:

Is the network connectivity between the two servers good? Also check the NIC settings. Try to copy some files from the media server to the remote server.

http://support.veritas.com/docs/237444
http://support.veritas.com/docs/249090

Revert with details if the issue persists.

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.

[Ken_Putnam]

Verify that AutoNegotiate is NOT enabled on NICs and Switch Ports. At least one end of each pipe should be hardset. I prefer to hardset both ends.

[Ajit_Kulkarni]

Hello Jason,


Can you please update the status of the issue ?


Regards

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.

[Jason_Dean]

Ok well I removed the MS Updates from the remote server - I just wanted to confirm that they weren't the cause.

The problem persists - backup rate of around 170mb/min for data on the local machine and just 65mb/min for the remote server. I hadn't changed any NIC or switch settings to cause the problem, but will do some testing as suggested when the network is free this weekend. Fun!

Thanks,
Jason

[Ken_Putnam]

170 MB.min local? That't terrible.

From the devices tab, what are the settings for Block Size, Buffer Size, number of Buffers, the two single block options and the two write through options?

[Jason_Dean]

Hi

Yes it was more like 530 mb.min for local and 440 mb.min for remote before the problem started.

It's an AIT 64K drive with the following settings:

Block size - 64K
Buffer size - 64K
Buffer count - 10
High water count - 0

Write single block mode and Write SCSI pass through mode are both ticked, the read options are unticked.

Thanks,
Jason

[Systems_Admin]

"Verify that AutoNegotiate is NOT enabled on NICs and Switch Ports. At least one end of each pipe should be hardset. I prefer to hardset both ends."

Why do people advise this randomly? In my experience it makes no difference and actually complicates moves on your switch port.

[Ken_Putnam]

Because I've suffered the results of trying to stream data over pipes with AutoNegotiate on each end and different vendors invoved (in my case Bay Switches and Compaq NICs)

Regular network traffic was acceptable, if a little on the slow side, but BackupExec was getting between 1.5 and 3.0 MB/min That's right MegaBytes per minute, not Megabits per sec. Hardsetting both ends cleared that up.

You SHOULD be OK if you hardset your switch ports and leave the NICs in Auto. If you move your servers around enough for both ends hardset to cause problems, you are moving them around way too much.

I've been offering this advice to people with slow network backups for years and no one has ever said that it made no difference, while many report significant speed ups

[Ken_Putnam]

Untick the single block write and the passthru. The passthru options should only be used if the target device is on a SAN and single block write turns off buffering altogether. That is BackupExec will read 64K, write 64K, read 64K, etc

Buffer of 64K adn buffer count of 10 should be OK, but if it was me I'd set the buffer to at least 128K or possibly 256K, bearing in mind you need enough RAM to support this.