Arcserve transfer rates

[purepest]

Hi

I am running arcserve 2000 on a w2k DC. The backup is taking longer than what it should be.

It appears to be that when the mailboxes are getting backed up, the transfer rate drops from 190mb/min to about 5 ro 7 mb/min.

We have ran a cleaning tape through the drive and that hasn't made any difference and we stopped the prune job

Anyone got any ideas

Colin

 

[ntinlin]

If these are brick level mailbox backups you are talking about then they will be VERY slow since the agent has to interface with Exchange through MAPI.
You take a massive hit because you aren't able to keep the drive supplied with enough data.
Therefore the tape constantly has to be wound back to start the next section of data. Very time consuming.

My speed drops from 380MB/min to 45MB/min when it hits the mailboxes.

Think it is worse if mailbox has lots of little attachments etc.
Although I must agree that 7MB/min is pretty awful.

Neill

 

[purepest]

thanks for that

I have just looked at the backup and it is backing up the registry of a remote server and the transfer rate is only 4.25mb/min


aaarrrrggghhhh! nightmare (and annoying)

 

[ACiDelic]

Besides MAPI slowing things down the anti-virus softare you are running can hampering performance as well. A lot of AV software implements VSAPI (Virus Scanning API) scanning to scan messages in Exchange. A brick level backup will request every message and the AV will have to scan each one in turn. This can severly affect performacne and you will most likely see it as as steadily decreasing transfer rate. This is caused by a backlog in the AV scanning since AV cannot keep up with Exchange and ARCserve.

Seeing as you are getting 4.25MB/min I think this is affecting you. You should at least try some of these suggestions. Depending on the AV software and the version of Exchange you are running you have a couple of options.

If you are lucky enough to be using Exchange 2000 or 2003 along with eTrust you are in luck. You can configure eTrust to exclude ARCserve applications from the scanning engine. This is specific to the Exchange scanning, not the file system. I'm not familiar with other AV softare, but most of the enterprise/corporate level software should offer application exclusion options.

If you are running Exchange 5.5 or using AV software that does not allow you to exclude processes from scanning then you are out of luck. Microsoft did a very poor job of implementing VSAPI in Exchange 5.5 and it is impossible for ANY AV software to exclude processes. You would need to stop AV (the part that scans Exchange) during the backups. If your AV software doesn't allow you to exclude processes you should change vendors or you'll have to stop AV during backups.

In either case you should make sure AV is not in the picture. A quick test without AV should show you if it the leading cause of bad BL performance. You should in reality see performance between 50-100MB depending on the capability of your hardware, the activity of the server and the configuration.

 

[fran5]

are you backing up through the network? or is your tape drive local to your machine?
Brick level backups should not be that slow.
Through the network, I get 198MB a minute
On a server with local tape drive - 131MB per minute.
Tell me what your set up is maybe I can help.

 

[purepest]

Thanks

There are 3 machines in this backup and they are all IBM servers with w2k server on them. The backup software is ARCserve 2000 which is installed on the domain controller.

The job backs up the C drive, registry and system state data on all of them.

On the exchange server we backup the information stores and do the brick level backup.

On the domain controller we backup another couple of local drives

On the file and print server we just back up the local drives to that machine as well. Nothing fancy.

As mentioned in an earlier post, we are running Symantec Corporate edition for out antivirus software on all 3 boxes and we also have symantec for exchange (MS 40) on the exchange box.

Thats all I can think of at the moment

If you have any more questions then please ask

Thanks again
Colin

 

[ACiDelic]

Disable Symantec for Exchange and run a test backup of just brick level. Your transfer rate will increase.

I'm not familiar with Symantec. Look in their documentation or online support to see if you exclude ARCserve from Exchange real time checking.

 

[argn]

As a suggestion purepest, why would you need to backup the registry separate from the system state. If you were required to restore a system the system state would hold a copy of the registry anyway.