Network backup (fbackup). Problem!!!!

[Sheshin]

I`ve got: Server1 (HP-UX 11.23) with StorageWorks 1/8 Tape Autoloader connected to it & Server2 (HP-UX 11.23).
When performing the backup of Server1 ( #fbackup -f /dev/rmt/0m -i /opt 2>>/backup.log ) , tape is recorded for 3 minutes (3.5Gb)., while when performing the backup of Server2 through the network (#fbackup -f Server1_IP:/dev/rmt/0m -i /opt 2>>/backup.log) , the tape is recorded within several hours (3.5 Gb as well) . When performing the backup from Server2 to Server1:/dev/rmt/0m through a crossover cable the backup also lasts for several hours. Are there any ideas what the problem is?

[Steven E. Protter]

Shalom,

HP-UX can not share tape drives the way you are trying.

To write to server1's tape drive the process must be started on server1. Remote access is not granted and the OS does not provide a facility to accomplish this.

You will need to copy the files to server1 and then issue the command to back them up, or get a tape driver for server2.

SEP

[Pete Randall]

You mention nothing about the network infrastructure involved. 10Base/T? 100Base/T? Gigabit?

It seems to me that the network pipeline that you're trying to force the data through is too narrow.


Pete

[Sheshin]

Steven E. Protter, I do not quite agree

#man fbackup
....
There is slightly different behavior if remote devices are used. A device on the remote machine can be specified in the form machine:device fbackup creates a server process from /usr/sbin/rmt on the remote machine to access the tape device. If /usr/sbin/rmt does not exist on the remote system, fbackup creates a server process from /etc/rmt on the remote machine to access the tape device.
...

[Steven E. Protter]

Don't agree all you like.

Its not supported. I'm sure its possible to come up with a kludge that works.

I've seen a serviceguard configuration that might allow it. Check with the response center as to our disagreement.

I think more relavent however is Pete's band width question.

Regards,

SEP

[Sheshin]

Pete Randall, network infrastructure - 100Base/T. Crossover cable - Gigabit. Copy /opt (3.5Gb) by FTP through the network from Server2 to Server1 - several min.

[Pete Randall]

What type of tape drive do you have in your autoloader? DLT?


Pete

[Sheshin]

Pete, we have Ultrium LTO 2 400Gb data cartridge in our autoloader.

[Pete Randall]

Ultrium/DLT - the problem is they are streaming devices and, if you can't feed them data fast enough, the drive keeps on spinning well past where it last wrote. Then it has to stop, back up, find where it left off, and resume writing, only to have the same thing happen all over again. This can cause your backup times to increase by factors of 10 or more. It also causes tremendous wear and tear on the drive.


Pete

[Sheshin]

Pete, what is the way out for this problem?

[Pete Randall]

Get a drive installed on Server2/increase the network bandwidth/maybe even try a slower drive on Server1.


Pete

[OldSchool]

Its definitely a bandwidth issue.

While fbackup and sam (using fbackup) can use a remote device, its going to be limited to how fast you can pump data, and you can't move it fast enough to keep the device in streaming mode

Your best bet is to attach a drive to the second server, or get a shared library

[whiteknight]

Sheshin,

Each server has an individual tape drive will be a good solution, it will fix your issue.

If you want to have a shared backup, you may consider ESL library connected via SAN



WK.

[Sheshin]

About bandwidth: network infrastructure - 100Base/T and copy /opt (3.5Gb) by FTP through the network from Server2 to Server1 - SEVERAL MIN!!! So, network infrastructure is able to pump 3.5Gb for 3 min.