topic Re: remote backup in Operating System - OpenVMS

remote backup

Lokesh_2 — Tue, 27 Jan 2004 11:22:00 GMT

Hi ,

I want to take the remote backup on tape. Let me explain my problem in detail. I have a system A which has 3 disks , but no tape drive. I have system B , which is having tape drive MUA0 . Now I want to take image backup of all the 3 disks of A on tape drive of system B. The problem is whatever qualifier I use ( /label, /ignore=label , /noinit , /norewind...etc...) , the remote tape is always initialzed with blank label . i.e. after backup command completes, when I dismount & remount the tape, is shows blank label. I do not have any other backup layered product ( like ABS, SLS ..etc..) nor want to purchase them. The backup command I use on system A is :

$backup/image/log/ignore=(interlock,noback) $1$DIA0: B"system password"::$1$MUA0:dia.sav/save/label=b_bck

Please suggest how to take remote backup on tape. VMS version is 7.1 on both nodes.

Also , In documentation, I have read about network save set, which describes about Files-11 only. Does, it means, network save-sets cannot be created on tapes ??

Thanks & regards,
Lokesh

Re: remote backup

Ian Miller. — Tue, 27 Jan 2004 12:08:17 GMT

I vaguely remember a trick with running a convert on the target system but the details are lost with memory bitrot :-)
I think you have to limit the block size due to DAP limitations parhaps to less lan 32k.

See decuserve e.g.
http://eisner.encompasserve.org/htbin/dnqindexform?kw=remote+backup+to+tape&fh=1&mh=10

there may be something.

Re: remote backup

Dale A. Marcy — Tue, 27 Jan 2004 12:13:01 GMT

Lokesh,

I think the problem is with remotely mounting the tape. I have remotely backed up systems to disk and then moved the file to tape on the remote system. We also have used the remote tape facility in Multinet to remotely mount the tape and perform backups over the net. Are you using the Multinet IP stack or another?

Re: remote backup

Mac Lilley — Tue, 27 Jan 2004 12:13:04 GMT

Hello

AFAIK backup to remote node is only supported to disk. Depending on disk space you could do your image backup to a saveset on disk on the remote system and then copy that to tape. To restore you would need to do the reverse.

You could investigate freeware products that allow you to "serve" tape drives. There is a product called ZT available from http://vms.process.com/scripts/fileserve/fileserve.com?ZT . I have no experience of it but it may provide a solution to your problem.

HTH

ML

Re: remote backup

labadie_1 — Tue, 27 Jan 2004 12:41:47 GMT

You have 2 options, if the client or the server has the initiative

1) client starting:
the client has a procedure containing a
command similar to

$ backup input remote::"task=rmtape"/sav/block=4096

on the server (the node remote), the object rmtape will have

allocate tape
init tape
mount tape
convert sys$net/fdl=... tape:file.bck/fdl=...

this method has a drawback: if the allocate, init, mount... is too long, the backup will fail.

a better method is to let the server start

2) server starting
the server will have a procedure containing

allocate tape
init tape
mount tape
convert client::"task=rmtape"/fdl=... tape:file.bck/fdl=...

the object rmtape will have a command similar to

backup input sys$net:/save/block=4096

on the client side, you will create a net backup account (with sysprv and readall)

here the decnet link will be estblished only when the tape will be ready.
Decnet used to limit the save set size to 4096, I do not know if this still applies.

in the default account of this user, a procedure rmtape.com containing

$ backup/qualifier disk sys$net:/save/block=4096
$ exit

create a ncp obj (or in ncl a session control application)
mc ncp
def obj rmtape number 0 file rmtbck.com user nobody password invalid
set obj rmtape all

All this comes from old notes, but should apply.

Re: remote backup

Rob Buxton — Tue, 27 Jan 2004 19:40:34 GMT

Or, you purchase SLS which does remote backups.

Re: remote backup

Lokesh_2 — Wed, 28 Jan 2004 10:05:25 GMT

Hi all,

Many thanks for your kind suggestions. I have installed SLS now on my systems and using this (RDserver/rdclient) to take backup on remote tape.

Thanks & regards,
Lokesh