topic Re: Restoring from disk to disk in Operating System - OpenVMS

Restoring from disk to disk

Alon Jacob — Thu, 10 Mar 2005 09:33:17 GMT

The situation is this : I backup some files from on disk (production) to another daily, and I use BACKUP and not COPY for the backup date to be modified in the file's header. The output files are NOT save-sets.
The question is - if I need to restore those files, can I use COPY instead of BACKUP?

Thank-you.

Re: Restoring from disk to disk

Ian Miller. — Thu, 10 Mar 2005 10:01:09 GMT

You can always use BACKUP to copy files - it preserves the file dates. I guess you use /RECORD so the source file gets its backup date written?

Re: Restoring from disk to disk

Duncan Morris — Thu, 10 Mar 2005 12:33:57 GMT

Alon, there would be no problem with using COPY. The backup does not not use any special formatting, so the files are in the same format whether you use backup or copy. As Ian says, it is the dates in the header that will differ.

Re: Restoring from disk to disk

Mobeen_1 — Thu, 10 Mar 2005 13:08:08 GMT

Alon,
I would agree with both the posts.. i don't see any difference in doing either except for the reason highlighted...

Just a question.. do you folks think that there will be any real difference in terms of time taken to restore copy vs backup ?

I have done some tests previously and always found backup to be faster ? Any thoughts

rgds
Mobeen

Re: Restoring from disk to disk

Jeffery D. Urmann — Thu, 10 Mar 2005 15:24:35 GMT

I believe that file security will not copy either.?

Enjoy,

--Jeff

Re: Restoring from disk to disk

Jan van den Ende — Thu, 10 Mar 2005 16:11:55 GMT

Jeff, correct!

File security on COPY:
a. _no_ SYSPRV _nor_ holding Resource Identifier equal to owner of directory: User doing COPY will be owner. If present, default ACL applies.
b. SYSPRV (or GRPPRV & grpUIC of user corresponds to target) or holder of said Ident:
b1. previous version of file exists: use security of that
if not:
b2. ACL on directory that specifies security with OPTIONS=DEFAULT: use that
if not:
b3: copy security of target directory.

A. Using BACKUP without /OWNER :
executing user becomes owner, users' processes' default protection used.
B. BACKUP with /OWN=PARENT :
copy security of target directory
C. BACKUP with /OWNER=ORIGINAL :
use original security.

---------

In COPY (without explicitly specifying version) next higher version is created.
in BACKUP, original version (even if lower) is created, unless specifying /NEW

--- ususally BACKUP/NEW /OWN=ORIG will be the desired result upon Restore; /NEW/OWN=PAR upon importing from somewhere else.

hth,

Proost.

Have one on me.

Jan

Re: Restoring from disk to disk

Antoniov. — Fri, 11 Mar 2005 02:31:08 GMT

Agree.
I already used copy instead backup to restore some files.

Antonio Vigliotti

Re: Restoring from disk to disk

Alon Jacob — Fri, 11 Mar 2005 10:20:13 GMT

Answering the first two replies - we use BACKUP and not COPY in order to change the backup date in the file's header. I also tested it comparing to COPY and both work the same speed.
Anouther good reason mentioned is to keep the original owner_uic since these are database files.
I know I can use set file/owner command, but yet - why changing twice?

Thanks all.

Re: Restoring from disk to disk

Alon Jacob — Fri, 11 Mar 2005 10:22:24 GMT

Got all the answers I needed, and more.
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