topic Re: network backup? in Operating System - HP-UX

network backup?

fizan — Wed, 25 Nov 2009 16:47:34 GMT

we have two servers eg: server A and Server B
so for backup we will generate the tar -cvf in serverA and sftp to serverB, then from serverB will fire cmd as tar -rvf bcoz tape drive is connected only on serverB,

1, Is there any option to fire the tar backup directly from ServerA to the tape drive connected to ServerB

Re: network backup?

Matti_Kurkela — Wed, 25 Nov 2009 16:59:38 GMT

SFTP? So you're using SSH, right?

I have the feeling that reading the SSH FAQ might be useful... oh yes, please see:

http://www.employees.org/~satch/ssh/faq/ssh-faq-5.html#ss5.1

MK

Re: network backup?

Tim Nelson — Wed, 25 Nov 2009 18:13:32 GMT

you could use the rmt facility ( man rmt ) but I have never had any luck with it. very slow.

you could nfs mount the directory from serverA to serverB and skip the ftp/sftp step. and then allow serverA to remote into serverB and kick off the backup.

lots of options

Re: network backup?

Steven E. Protter — Wed, 25 Nov 2009 18:30:05 GMT

Shalom,

Tape drives are not shared devices that can be used by remote servers.

Serviceguard may offer this feature, but I've not seen that done.

Therefore the process must be two step.

1) Transfer the file or create it on the remote system that has the tape drive.
2) Start a process that writes the tar file to tape.

This link will help you set up your systems to do this without password prompts:
http://www.hpux.ws/?p=10

SEP

Re: network backup?

fizan — Wed, 25 Nov 2009 19:30:35 GMT

with out sharing it through NFS it is possible i want to know how it can be done.

Re: network backup?

OldSchool — Wed, 25 Nov 2009 20:21:01 GMT

read the link Matti posted re using ssh to "pipe" the output to a "dd" running on the remote server(with tape)

see Steven's regarding "passwordless" ssh...

that doesn't require any NFS mounts.

Re: network backup?

fizan — Wed, 25 Nov 2009 21:14:31 GMT

# tar cvf - | ssh user@host "dd of=/dev/tape"

tar -cvf /rman/backup |ssh test@10.10.49.30 "dd of=/dev/rmt1"

right, then for passwdless login
1. generate the public key of test from serverA and add it in the serverB s test users home directory's .ssh/authorised_keys

2.basically /rman/backup is present in serverA

Re: network backup?

Dennis Handly — Wed, 25 Nov 2009 22:23:52 GMT

>then from serverB will fire cmd as tar -rvf

You can't use -r for tape.

>SEP: Tape drives are not shared devices that can be used by remote servers.

I assume some industrial strength backup product like Data Protector allows for that?

Re: network backup?

Steven Schweda — Wed, 25 Nov 2009 22:42:55 GMT

> I assume some industrial strength backup
> product like Data Protector allows for
> that?

VMScluster.

http://h71000.www7.hp.com/doc/82final/aa-pv5nj-tk/00/00/87-con.html

You can use the OpenVMS MSCP, which is the
mass storage control protocol, or TMSCP,
which is the tape mass storage control
protocol, server software to make tapes
accessible to nodes that are not directly
connected to the storage devices.

Do it all the time.

alp $ show device /full dlt

Magtape ALP$MKB400:, device type Quantum DLT4000 CPQ DRV, is online, record-
oriented device, file-oriented device, served to cluster via TMSCP Server,
[...]

Or "man rmt", for a less feature-rich
environment.

Re: network backup?

fizan — Wed, 25 Nov 2009 22:51:29 GMT

experts what is the final conclusion,

whether i can run the following cmds as mentioned in the last scrap?

Re: network backup?

Dennis Handly — Wed, 25 Nov 2009 23:19:45 GMT

>whether I can run the following cmds as mentioned in the last scrap?

If you are going to use dd(1) to tape, you need a larger blocksize.
dd of=/dev/rmt1 obs=10k

This matches the tar(1) default of "-b 20".

Re: network backup?

fizan — Wed, 25 Nov 2009 23:34:19 GMT

normally we dont use this dd of cmd so i will refer it n use it,

can u gimme the tar excat syntax dennis? for this issue

Re: network backup?

Dennis Handly — Thu, 26 Nov 2009 00:42:30 GMT

>can you gimme the tar exact syntax for this issue

Oops, you probably need a "-" to send to stdout:
tar -cvf - /rman/backup | ssh test@10.10.49.30 "dd of=/dev/rmt1 obs=10k"

Re: network backup?

OldSchool — Thu, 26 Nov 2009 15:52:03 GMT

Dennis H: "I assume some industrial strength backup product like Data Protector allows for that?"

In a manner of speaking, yes.

DP installs a "media agent" on systems with locally attached tapes / libraries. A "disk agent" is installed on the client system. Disk agent pases data media agent which reads / writes tape.

With SAN attached tapes, you can mult-home the drives, reducing overhead