backup filesystem & raw devices using Remote tape drvie

[Marwan Kobbe]

I have an HPD370 UNIX system (ver 10.2). I need to backup the system and
database using the tape drive on another remote system. My specific question
is whether i can NFS mount the tape drive of the remote machine to the HPD370.
I have exported the "/dev " directory and mounted it (as a different name) on
the HPD370. I tried to use the device but i get the message: " could not open
the device" ...

Please let me know whether this is possible or not .. or what is the best
solution and alternative...

Thank you..

[Shyam Kishore_2]

Hi,

You can try mounting your filesystem on remote system where B/U device is
located for taking backup rather mounting the device files from that m/c. just
using the device files from remote system will not allow you to access the
remote devices.

-Shyam

[Terja Lange_1]

no,no,no, you cannot export /dev directory. Its special
The way around it is

use fbackup

with the option -f ${targetmachine}:$tapedev

where targetmachine is the machine with the tape drive and tape dev is the
device name on the remote machine.

[Dave Wherry_1]

Before you waste too much time, you said you want to backup raw devices. As
far as I know fbackup does not do raw and you can not nfs export a raw device.
What are you using to back these up? OmniBack can use remote tape devices for
raw. Whatever you are using you should be able to run it locally and then pipe
the results to the remote device using cpio.
Sorry, I can't te4ll you the syntax off hand. It would be something like:
local backup routine | cpio -??? remotehost:/dev/rmt/0m
Maybe some one else can fill in the blanks.

[Bill Hassell]

NFS (ie, mounting a remote filesystem) only applies to a real disk-based filesystem. There is no such concept as mounting the /dev directory and using the remote device files.

fbackup provides remote tape access *but* the remote system must have fbackup installed and must allow remsh access through $HOME/.rhosts in order to work. Tapes made using a remote drive will not have high speed search marks included so data recovery can be 100 to 1000 times slower than tapes recorded locally (the tapes must be read serially).

[Stefan Stechemesser]

try the following without use of NFS:

1.) insert the hostname of the computer to backup in the /.rhost file of the remote system (hope it is hpux)
2.) log in as root
3.) backup with
tar -cvf - * | remsh remotehostname /usr/bin/dd of=/dev/rmt/0m

if /dev/rmt/0m is your tape device on the remote system.

You can use any backup program which can write to stdout. To reduce network traffic,
you can also try:
3.) tar -cvf - * | gzip -c -9 | remsh remotehostname dd of=/dev/rmt/0m

This should work not only on HPUX but on all Unix machines (maybe the commands vary, rsh, rexec)

[Mike Plunkett]

I nfs-mount all the file systems that need to be backed up onto the machine with the tape drive. Then I direct the backup software to backup those nfs-mounted filesystems.

mp