Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations TouchToneTommy on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

How to Copy save_set from Tape to Disk 1

Status
Not open for further replies.

walsham

Programmer
Aug 20, 2004
1
US
I am a new Vax user (stange I know). I am running OPenVMS 5.5-2. Weekly we create savesets by writing them directly to tape. What I would like to do, is copy these savesets from the tape to disk, so that I cn FTP them to another VAX on 5.5-2 and restore them there. However when I try to
mount $mua1:

and then do a

copy $mua1:[000000]foobar.sav $10$dua10[save_set_test]foobar.sav

I get RMS errors, complaining the block size is wrong. I know that the block size used to create the backup is 16634 (?).
I was thinking that

MOUNT /FOREIGN/BLOCK=16634/RECORD=512 $mua1:

then a

copy $mua1:[000000]foobar.sav $10$dua10[save_set_test]foobar.sav

would that work? can you do a copy with a foreign mount? also how do I determine the correct block size to use?

Thank
Aaron
 
I too am relatively new to VMS so take my advice with caution. I think I'd do the following:

backup/rew/list mua1:

I believe the tape attributes and backup stats are listed in the first few lines of the response.


mike
 
I just tried it on one of my machines (an alpha, admittedly, but in theory it should be the same), and copying the file while the tape is mounted /OVER=ID works fine... mounted /FOREIGN does NOT work - data overrun errors...

<HOOROO~Hugh~1>mount/over=id mka400
%MOUNT-I-MOUNTED, H2501 mounted on _HOOROO$MKA400:

<HOOROO~Hugh~1>copy/log mka400:[000000]*.bck sys$login:
%COPY-S-COPIED, MKA400:[]HUGH.BCK;1 copied to SUPPORT_USERS:[SAMSON_H]HUGH.BCK;3 (24802 records)

<HOOROO~Hugh~1>back/lis sys$login:hugh.bck/sav
Listing of save set(s)
(listing is output correctly - shows copy of saveset on disk is OK)

<HOOROO~Hugh~1>dism/nounl mka400

<HOOROO~Hugh~1>mount/for mka400
%MOUNT-I-MOUNTED, H2501 mounted on _HOOROO$MKA400:

<HOOROO~Hugh~1>copy/log mka400:[000000]*.bck sys$login:;
%COPY-S-COPIED, _HOOROO$MKA400: copied to SUPPORT_USERS:[SAMSON_H].;1 (3 records)
%COPY-E-READERR, error reading MKA400:[000000:[].;
-RMS-F-RER, file read error
-SYSTEM-W-DATAOVERUN, data overrun
%COPY-W-NOTCMPLT, MKA400:[000000:[].; not completely copied
%COPY-W-NOTCMPLT, MKA400:[000000:[SAMSON_H].; not completely copied

<HOOROO~Hugh~1>dism/nounl mka400

Did all of the above without touching the attributes at all - the drive works this out when it mounts the tape, so you shouldn't have to do anything. You really only need to specif the blocksize when mounting a non-VMS tape/disk/etc in foreign mode.
 
You cannot use the copy command to copy savesets from the tape. As you found out, you will get RMS errors if you try.

The reason is because when savesets are written to tape, if VMS backup encouners a minor problem writing to tape (for example, if it hits end of tape), then it will rewrite the data again.

The copy command cannot take into account any issues when writing the data onto tape.

There is a layered product that can be used to properly copy backup savesets. This is called Saveset Manager. I personally used this product back when it was still in beta stage (over 10 yrs ago) and it does work.

 
Actually, you can copy savesets from tape to disk. The tape has to be mounted normally, not foreign and the block size needs to be 32767 or less.

Yes, there is the problem if backup got around a bad spot on the tape, but with the newer DLT type tape drives that hardly ever happens anymore.

In fact, the company where I'm now working uses tape to disk copy as part of their disaster recovery scheme.

Ken Robinson
OpenVMS System Mananger (for over 20 years)
 
kenrbrsn, because you pointed out that it is possible for problems to occur when writing to tape, this shows that copy is not foolproof.

And considering that we are talking about backups savesets, I cannot recommend to a fellow colleague to use a method that does not work 100%.

Is using copy supported or recommended by HP? The answer is most likely no, and this was one of the reasons why Saveset Manager was created.

As for tape drive reliability, even with the newer tape drives has not eliminated the occurances of i/o errors when reading or writing to tape.

So... will copy work? Not always...
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top