Problem in backup

[Hoff]

>Any quick suggestion?

Yes. Stop using BACKUP. Go try the BACKUP$MANAGER utility. The latter approach is somewhat better suited for more modern preferences toward computing interfaces. The syntax of the former is as close as OpenVMS gets to a Unix bash shell command; it's cryptic and somewhat hazardous.

[Swain]

Hi,

Thanks for all your help!

I used following command.

BACKUP/IGNORE=(INTERLOCK,LABEL)/NOCRC/RECORD/NOASSIST/VERIFY NUS$DKD400:[000000...]/BY_OWNER='UIC' NUS$MKC600:'USER'.SAV/MEDIA_FORMAT=COMPACT

It works fine. But it's very slow. Any suggestion for performance improvement ?

Thanks,
Amaresh

[Steven Schweda]

> [...] But it's very slow. [...]

Define "very slow".

You're asking BACKUP to scan the whole disk,
looking for files owned by UIC. Did you
expect that to be very fast? And then, I
assume, you do it for more than one UIC.

Why are you using /BY_OWNER here? How useful
is it to make a separate save set for each
user?

[Jon Pinkley]

Use the /FAST qualifier (no kidding, see HELP BACKUP/FAST)

In the backup command you gave, you are requesting that backup look at every file on the disk to see if it is owned by the specified UIC. The /FAST qualifier tells VMS BACKUP to scan the indexf.sys file to find all the files to backup, so it does not have to do a complete directory tree traversal. This will be faster than the command without /FAST. For image backups, /FAST is the default.

Unless you restore files much more frequently than you make backups, then if you want to save time, do not use individual backup savesets for each UIC, unless you are only backing up a small subset of all user UICs.

While your example command will backup all the files owned by the user, why are files owned by a specific UIC spread all over? That is not typical, and implies that directory protections may be a bit more lax than normal.

Jon

[Volker Halle]

Amaresh,

unless you describe the purpose and use of this type of 'per-user' backup, you cannot really expect useful suggestions.

BACKUP is normally used to save data, which you hope to never need to restore, so you try to speed up your save operation and use a BACKUP/IMAGE, to make sure you've saved all the data on disk. Then - if the need arises - you can restore individual user's files from that image-backup.

But there may be other uses for BACKUP and your's may be a special case. If so, then please explain...

Volker.

[Swain]

Hi All,

Thanks a lot for your suggestions.

> unless you describe the purpose and use of this type of 'per-user' backup, you cannot really expect useful suggestions.

This is a disk clean activity to avoid space issues. There are 300 disabled users on this system. We are archiving old data of disusers, which may need a user specific restore if we need to make these users return (/flags=nodisuser) in future.

> Define "very slow".

Thanks for describing the reason. Now I got the answer.

I am doing it for first time. Please nvm.

Thanks,
Amaresh

[Steven Schweda]

> [...] may need a user specific restore
> [...]

Does that require separate, user-specific
saves? Does each user have files scattered
all over? What you're doing may make sense,
but it's not obvious that it does.

[Swain]

Hey Steve,

Please let me know how can I restore files owned by a single user/UIC from an image backup of the whole user_disk(DKD400).

Thanks,
Amaresh

[Richard Brodie_1]

Something like:

$ BACKUP/VERIFY NUS$MKC600:JZIEGLER.SAV /BY_OWNER=[130,220] NUS$DKD400:[000000...]

[Steven Schweda]

> Something like:
> [...] /BY_OWNER= [...]

Not really. HELP BACKUP /BY_OWNER explains
the difference between /BY_OWNER as an input
file-selection qualifier and as an output
file (or save set) qualifier.

> [...] Does each user have files scattered
> all over? [...]

If so, then you may need to do what you
propose. In my experience, it generally
makes more sense to divide the data by
function (often by top-level directory) than
by owner, but your situation may be
different.