topic Re: ABS LOOKUP Question in Operating System - OpenVMS

ABS LOOKUP Question

Piet Timmers — Tue, 27 Apr 2004 07:57:20 GMT

Hi there,

See the following include spec (ABS):

Include Spec - DISKXX:
Source Node - NODE1
Object Type - VMS_FILES
Exclude Spec - None
Agent Qual. - /PHYSICAL/BLOCK_SIZE=65535/NOIMAGE

So I get a physical backup instead an image backup. What is het ABS LOOKUP command to use when I want to find out on which tape this physical backup is stored on. I have use many options, but none showed me want I need.

Greetings,

Piet

Re: ABS LOOKUP Question

Antoniov. — Tue, 27 Apr 2004 10:20:32 GMT

Hi Piet,
I don't know ABS so I can only indirectly answer you.
BACKUP/PHY makes a physical copy of device and you can make this only between same type of devices; this means you can't backup a disk onto tape; looking at your post I read /PHY and /BLOCK_SIZE qualifier that are incompatibles.
Perhaps, ABS may have not this contraint but however why you wish physical backup changing block size?

@Antoniov

Re: ABS LOOKUP Question

Uwe Zessin — Tue, 27 Apr 2004 10:50:12 GMT

Well, I don't know ABS either - welcome to the club ;-)

But I am sure I have taken a physical backup of a disk and stored it in a BACKUP saveset.

Re: ABS LOOKUP Question

Piet Timmers — Wed, 28 Apr 2004 01:09:48 GMT

ABS uses "normal" backup commands to save the data to a tape. A physical backup creates a normal backup saveset, so it can be made to tape.

Re: ABS LOOKUP Question

Uwe Zessin — Wed, 28 Apr 2004 01:12:31 GMT

That's what I thought, thanks for confirming it.

Re: ABS LOOKUP Question

Antoniov. — Wed, 28 Apr 2004 02:16:00 GMT

Hi Piet,
I use physical backup from disk to disk to make a full identical copy. On disk, physical backup doesn't create a saveset.
I never tryed from disk to tape, so I'm not sure about this but if you type HELP BACKUP /PHYS I guess you can't backup form disk to tape.

@Antoniov

Re: ABS LOOKUP Question

Uwe Zessin — Wed, 28 Apr 2004 02:42:05 GMT

Antoniov,
it _is_ possible to copy a physical backup into a saveset and restore from it. When BACKUP writes to tape it always creates a saveset. I will attach a small session to illustrate (I don't have a tape connected, so the saveset is on disk).

Re: ABS LOOKUP Question

Piet Timmers — Wed, 28 Apr 2004 02:45:56 GMT

Hi,

---------------------------------------------
$ help backup/physical
BACKUP

/PHYSICAL

Command Qualifier

Specifies that the BACKUP ignore any file structure on the volume
and to process the volume in terms of physical blocks. If you
write a save set with the BACKUP/PHYSICAL command, you must also
restore it with the BACKUP/PHYSICAL command.
---------------------------------------------

So, a physical backup can write a saveset.

$ backup/physical disk: tape:saveset.bck/save will create a saveset on tape, containig a physical backup from the disk.

But, that is not the question/discussion i started.

Greetings.

Re: ABS LOOKUP Question

Antoniov. — Wed, 28 Apr 2004 03:37:52 GMT

Hi Piet,

So, a physical backup can write a saveset.
[...]
But, that is not the question/discussion i started.

savet may inherit from your question; if you can, post the full command ABS use to backup. Because physical backup onto saveset was not not supported in old version of vms, may be ABS retain command.

@Antoniov

Re: ABS LOOKUP Question

Piet Timmers — Wed, 28 Apr 2004 03:57:39 GMT

Ok, extracted from the ABS log file:

$ BACKUP /IMAGE DISKXX: -
/LIST=_MBA9676:/FULL -
/IGNORE=(INTERLOCK) -
/NOCRC/NOVERIFY -
'SHELVE_QUAL''ALIAS_QUAL' -
/PHYSICAL/BLOCK_SIZE=65535/NOIMAGE -
$2$MGA0:28APR20040351240./SAVE -
/EXACT_ORDER -
/STOR=V2SLS/NOASSIST

btw: I have posted a few weeks ago a question about the elapsed for a backup, in our case 9 hours. HP specialist gave as advise, use physical backup instead image backup, backup time is now 45 minutes.

Re: ABS LOOKUP Question

Uwe Zessin — Wed, 28 Apr 2004 04:07:45 GMT

Is the /PHYSICAL backup run on a mounted volume while users are working on it? I hope you understand that a /IMAGE/IGNORE=(INTERLOCK) might save inconsistent files, but a /PHYSICAL backup does not even know what a file is.

You cannot retrieve single files from it and you might restore a corrupted disk, because there is not even a synchronization with mete-data updates!!

Re: ABS LOOKUP Question

Piet Timmers — Wed, 28 Apr 2004 04:35:40 GMT

We know, but is the only solution to our problem to make the elapsed time acceptable. I know it is impossible to restore single files, so I want to restore the whole disk to another (spare) disk. And that is when I need to know on which tape, and saveset, ABS has saved this backup. I can get this information reading the ABS loggfiles, but we keep only two versions.

Piet

Re: ABS LOOKUP Question

Antoniov. — Wed, 28 Apr 2004 04:49:39 GMT

Hi Piet,

HP specialist gave as advise, use physical backup instead image backup

Backup /PHYS make a copy of all records on disk even they are unused by file system.
Backup /IMAGE read only records of files and folder.
So if you have a quite full disk, /PHYS may run quicker because backup reads sequentally while if your disk has a lot of free space /IMAGE may make quicker because has less record to read.
Sorry for broken english explain, I hope you can understand.

Because /PHYS and /IMAGE are mutually exclusive, type /NOIMAGE before /PHYS in your agent qualifier: may be DCL find any syntax error parsing /PHYS after /IMAGE and before /NOIMAGE.

Again,
using /IGNORE=INTERLOCK is very very dangerous and doesn't grant you a good copy.

@Antoniov

Re: ABS LOOKUP Question

Ian Miller. — Wed, 28 Apr 2004 05:14:18 GMT

I think the original question is "How to find which tape contains the backup wanted". In SLS this would be done with a STORAGE REPORT SYSTEM command. In ABS I know not :-(