NFS mount /dev/rmt files?

[Terry Kummell]

Hi,

I would like to use a tape device (dds 3) on one of our HP 9000 servers from a new L-2000 we are installing. Is it possible to mount the device files such as /dev/rmt/2mn? If not, is there some other way to accomplish this function?

My thoughts are to use an 'extra' dds tapedrive on an older server as an informix logging tape and then schedule the backups for the dds-3 that is installed in the L-2000.

Possible?

Regards,

Terry Kummell
CCITriad

[Shannon Petry · Accepted solution]

Yes there is a way to do this, but not by mounting devices. This would be the equivalent to mount /dev/tty0p0 to use a modem, or /dev/dsk/c1t1d0 to access a disk drive......does not work because these are devices!

What you can do us use remsh to pipe output to a tape, and input from a tape...I.E (I'll use hp1 and L1)

To put files to tape
L1> tar cvf - ./* | remsh hp1 'dd of=/dev/rmt/0m'
To get files from tape
L1> remsh hp1 'dd if=/dev/rmt0m' | tar xvf -

If you use fbackup, it supports remote devices on other HP systems, as well as local. Most backup utilities also support remote devices such as Omniback, Legatto, and Tivoli.

Hope it helps
Shannon

[A. Clay Stephenson]

Hi Terry,

Shannon has given you the workaround. This is one of the few area's where System V's old RFS (Remote File System) beats NFS; it was possible to mount remote devices.

Regards, Clay

[Patrick Wallek]

If you use fbackup to do a backup of your system, you can use a remote tape device as well.

I'm not at my unix machine so I can't tell you the fbackup syntax exactly, but when you specify the tape drive in the fbackup command line you use a device file like 'system:/dev/rmt/?mn'

[Terry Kummell]

Hmmmm, now I see how to accomplish backups on a 'remote' tape drive. However, after re-reading my original post, I see that I wasn't clear as to what I was really trying to accomplish. Let me try again:

I have a new L class server (an L-2000). It only has one DDS-3 tape drive. We run informix here and need a dedicated tape drive to cut database log records on through out the day (24 hour operation). I had hoped that there might be some way to use a 'spare' DDS-3 drive on one of the older servers (a T600) to do this logging task. This would free up the 'local' DDS-3 tape drive to do backups.

From the responses I got, it looks like I could do backups on the 'remote' tape drive. Anyone have any experience with backups over a 10MBit network?

Thank you all for your help on this. I think I'll go try that backup right now. To see how long it's gonna take.....

Regard,

Terry

[Emil Velez]

Device files cannot be used remotely to access remote devices. When you reference a device file it makes the kernel use a local device since a device file is a file with no data just a driver and parameters (address).

fbackup on hpux using remsh writes to remote devices but that uses remsh.

[avsrinivas_1]

I have done the similar setup between HP E45 and D230 between HPUX 9.04 and 10.20. The network is also 10Mbps Thinnet. What exactly i have done is, given root access for one machine to other through /.rhosts file.
then i used fbackup with -f machine:device switch.

I have taken backup and restored the same. The things are still working fine.

but regarding informix i dont have idea whether
it uses fbackup or not.