VMS backup

[Tony Cullen]

I would like to know the backup qualifier to list just the save sets on a tape.
Backup/list gives the save set contents and i just want to confirm the existence of the sets themselves.

[Ian Miller. · Accepted solution]

You can just use DIR if you moun the tape normally.
e.g

$ MOUNT MKA500: LABEL
$ DIR MKA500:*.*

[Tony Cullen]

Thanks Ian, I should have remembered.

I am doing a DR test and have a tape with image backups of our volumes.
I have in the past I have always used /sav when restoring from image. e.g.
backup/image/rew/sav mkb100:dsa0.bck/sav dke0:
This time I got a message %backup-iods2compat, output vol dkf0: structure ods-2 is not compatible with ovms vers prior to 7.2. The backup then aborted and only ctrl-c stopped the process.
My system is running 7.2-2.
I removed /sav from the command and still got the message but the backup did proceed. Is /sav not required after release 7.2?

[Ian Miller.]

/SAVE is default if device is a tape drive.

The message %backup-i-ods2compat

Tells you the volume backed up has a storage bitmap too big for Pre V7.2 systems to handle. As its a informational message then thats not the reason your backup then aborted.

[Martin P.J. Zinser]

Hello Tony,

as Ian pointed out the message you quoted should be harmless, see help/mess for a bit
wordier explanation.

Exactly what command did you try to execute and exactly which messages did you get?

Greetings, Martin

[Uwe Zessin]

Watch out!

A command like:
$ directory tape:*.*

can show your tape contents two more more times if your current default is a logical name search list. The reason is that the command did not give a directory specification and the system is pulling one from every entry of the search list. If I recall correctly, you can easily avoid this with:

$ directory tape:[]*.*

[Bojan Nemec]

And if you forgot the tape label you can mount with this command:

$ MOUNT/OVERRIDE=IDENTIFICATION MKA500:

Bojan

[Antoniov.]

Hi Tony,
you are restoring image backup, so target disk will be same structure of old source disk; I guess you restore operation try to change disk structure so I think you must confirm this choice.
You could type follow commands:
$ mount dke0: /fore
$ mount mkb100:/fore
$ backup/image/rew mkb100:dsa0.bck/sav dke0:/init

Apparently you don't need /init but you can try using it.

Antonio Vigliotti

[Uwe Zessin]

Antonio,
it looks to me he wants to find out the filenames on the tape - not restore any data.

But that reminds me about some other 'tricks?'. You can list all contents on a tape with:
$ backup /list=backup.lis tape:*.* /log

With the /LOG qualifier you get a message whenever BACKUP sees a new saveset on tape.

Once you have the list you can search it with:
$ search backup.lis "Save set:".


I think it will be much slower, because backup has to read and process all savesets and their contents, while a 'DIRECTORY' can have the ACP jump between tape marks.

[Antoniov.]

Uwe,
if you only will a file list you couldn't use /log qualifier because this option say what you have backuped (or restored) and need target device.
Backup/list is unique way to read source tape saveset without restore.

Antonio Vigliotti

[Uwe Zessin]

Antonio,
you have misunderstood my comment (or I expressed it badly).

The purpose of the /LOG qualifier in my example was to receive a message like:

%BACKUP-I-NEWSAVSET, now beginning save set 'A.BCK'

(I don't have a tape drive, so I have tried to construct that message. Apologies if it looks different.)

[Chris Davis_9]

Hi Tony,

I'm sorry that I don't know of any command apart from those listed to confirm the existence of the save sets and their names. I usually use BACK/LIST TAPE: if I need to, then Ctrl^O to turn off display. Our save sets have pre-determined names with a date element and these are documented in our DR procedures, so once the first save-set date is known, all other save-set names are known.

When you got the ODS2 incompatible message, was the machine you were restoring onto booted with a prior version of VMS? This sometimes happens in a DR situation when the hardware provider hasn't upgraded or just happens to be booted from a prior version.

You would then get the warning message because the system recognises that the disk you are preparing would not be mountable on the system (as it's currently running a prior version).

It's worth ensuring that your DR provider has your current version of VMS booted for recovery purposes, there have been differences between the backup command in prior versions of VMS, not usually show stoppers, but perhaps with default values or actions.

As already pointed out, this is an informational message only and shouldn't stop the restore taking place. I always use the /LOG qualifier to ensure the restore is happening, then again turn off the display with Ctrl^O.

I've been doing DR tests on VMS since 1986, so feel free to contact me offline. My email is chris.davis@pmas.co.uk

Hope this helps for future recoveries!