Slow job rate using backup to disk.

[Chizzad]

Here is my scenario.  I have 2 ioSafe hazard proff 1TB external hdd's.  One is on sight and works great, runs daily and monthly backups with average job rates of 550-600 mb/min.  Since our backups are 110gb this is fine for us as they take about 4-5 hours to complete over night.

My problem comes in with our other server that is at our offsite location (across the street).  This has the same external drive and has an esata connection which should be faster than usb 2.0 which the on site server is using.  My speeds on this server though are around 80-100mb/min.  At this rate the exact same backup takes about a day and a half (35-40 hours).  I have tried swapping cables, tried using usb and the esata, looked at the NIC properties and the connection properties, all of these settings appear to be fine. 

The onsite server is running windows server 2003 R2 SP2 and the offsite server is running Microsoft Windows Server 2003 for Small Business Server SP2.  The onsite server (the faster one) has a Broadcom BCM5708C NetXtreme II GigE NIC, and the offsite (slow server) has a Broadcom NetXtreme Gigabit Ethernet NIC. 

I realize this could be caused by numerous other factors and can give any additional information to try and figure this out. 

What would cause one to run at 500-600mb/min and the other to run at 80-100mb/min?

Thanks in advance!

[pkh]

Two common factors that can cause a slow backup rate are numerous small files and disk fragmentation.

[Chizzad]

Still looking for some input on this, disk defragmentation and numerous small files are not the cause, as stated earlier, the 2 backups are doing the exact same backup, pulling the files from the same spots.  Thanks.

[ZeRoC00L]

What is the source data you are trying to backup ?
Is it located on each server with the backup2disk device connected to ?

Is backup exec installed on both servers ?

What is the connection between the servers?

[Chizzad]

The source data we are trying to backup is system state, SQL server, Information Store One (Exchange), and our shared drives.  Total amount of data is 112 GB's.

The information is all on server one, the backup to disk is located on servers two and three respectively.

Backup exec is only installed on server one which neither backup drive is attached to.

Both external hdd's are currently attached via usb 2.0.  One has rates of 500-600 MB/min. the other has 80-100 MB/min.

The server with the slow speeds is across the street away from our server room, we have got speeds over 100 MB/min. but it usually averages to about 100 MB/min.

I "believe" the connection between the offsite server and the main server room is wireless N connection.

[ZeRoC00L]

If you copy data from the 'problem' server to the usb disk, how fast does it copy the data ?

But if 'another' server manages the backup, all data will bass through that server, and therefore the speed is limited by this server.

[Chizzad]

The rate of transfer from the problem server to the usb disk (which is directly attached to the server) is 14.3 MB/sec, so that is not the culprit.  The server that manages the backup manages 2 backups though, one with 500-600 MB/min speeds and another with 80-100 MB/min.

[ZeRoC00L]

Because the server that magages the backup is in building 1, all data must be transferred twice via your wifi connection, once to the backup server, and back to the usb disk. That's why it is slow.

You should install another instance (and thus require a license, but you can try for 60 days) of Backup Exec onto the 'problem' server and see if that speeds up the backup.

[Chizzad]

I think you are right, we have tried everything else.  I think it is because of the wireless, it is wireless G, which is "supposed" to have speeds up to 54 Mbps, but like you said it is going to server than to external so this is probably the cause.  Another license is like $1100 though.... So might be better off upgrading to wireless N, that could help.  Or get another license as you suggested, we will try to install the trial just to see if it fixes the problem.

[ZeRoC00L]

Yes, I suggest to do a test first, and see if that solves the issue. Then you, or your management can decide if their data is worth a $1000 to be safe :)

[Chizzad]

Well even with the slow speeds, it can complete the backup in 1 1/2 days so I just set it up for one weekly and one monthly backup for now till we get the speed increased.  But yah I agree, $1000 to prevent crippling data loss in my opinion is a no brainer.

[teiva-boy]

If you are not using a DIRECTIONAL antenna with your wireless access point, you will NEVER see the speeds advertised for wireless.  A fart in front of a non-directional antenna will drop throughput 30%.  It's that sensitive.

You should have the external directional antenna's pointing at each other.  If you have to encrypt the connection (which you should) it will cut throughput by 50% in most chceap access points.

[OP]

Hi Chizzad,

I would suggest to find out the maximum available network-speed between the source-server and the 2 backuptarget-servers.

After that you are able to see if the backup is the problem or the network.

iperf could do that job..

Regards

O.