Backup, Encryption, & NotANSI

[Aaron Sakovich]

OpenVMS 8.3-1H1, Itanium rx2620, Compaq SDLT 320 tape drive.

I pop in a new tape, init it, mount it /foreign, and issue the following backup command:

$ backup [...]*.*.* tape$sdlt:backup.bck/save/media=compact/label=backup/block=32768/encrypt

Works fine. Dismount/nounload, go through the *exact* same process again, and as soon as I hit on the backup command, I get this:

%BACKUP-F-LABELERR, error in tape label processing on MKB600:[000000]backu
p.bck;
-BACKUP-F-NOTANSI, tape is not valid ANSI format

No errors are logged by the system -- just the mounts/dismounts.

The tape, at that point, is unusable. I can put in a new tape and it works fine. (I have power cycled the tape drive in between new tapes, but don't want to waste more tapes just to find out that it does/doesn't need a power cycle.)

I've searched the ECOs, to no avail. Same with these forums, c.o.v., and the web too. Scoured the docu, no joy.

Any ideas? Anything obvious that I might be doing wrong? Any ideas on what to look for?

[Robert Gezelter]

Aaron,

With all due respect, at least two suggestions:

- MOUNT/FOREIGN and then DUMP the first several blocks of the tape to see what is actually on the tape.

- See if the problem recurs when used with the logical tape support that is part of the LDDRIVER (if it reproduces, at least it will be wasting virtual tapes, which are 100% recycleable)

- Bob Gezelter, http://www.rlgsc.com

[Aaron Sakovich]

Which version of LD supports virtual tapes? I'm running 8.2, which is what came with 8.3-1H1. I see nothing in the online help about connecting virtual tape devices. I can not load non-HP kits on this system, either.

Unfortunately, the guy handling the tapes for me (100+ miles away) has already swapped out the bad one, so dumping it's a moot point at this time.

[Jon Pinkley]

Aaron,

LD 9.0 or later supports the LM (logical magtape) devices. You will need at least V9.1 to install on 8.3-1H1. V9.3 is current as of this time.

They are available on Jur's site www.digiater.nl

>>>"The tape, at that point, is unusable."

Does that mean:

1. You can't use backup to append another saveset to the tape.

2. You can't read the existing backup saveset you just created.

3. The tape can't be reinitialized.

4. The tape self destructs like on mission impossible.

5. Something else.

Jon

[Aaron Sakovich]

The tape self-destructs, like on Mission Impossible. (lol) Thanks for the chuckle!

Seriously, tho, it can be initialized and mounted, but try to do anything to it using Backup, and I get the error mentioned above.

Thanks for the info on the new LD version -- sadly, I can't use it on this system. I may be able to load it on one of my test boxes, though, and will investigate that next week!

[Hoff]

Same SDLT tape drive for both operations?

What particular SDLT media?

Please post the DCL commands used for the tape creation (including the INITIALIZE and the MOUNT), and the DCL commands used to (try to) access the contents.

The DUMP of the first few records of the tape might help; I'd expect the headers here should be cleartext with a typical BACKUP, whether with encryption in use or otherwise.

Load the ECO kits, too. UPDATE, and anything else involved with SCSI, backup, mount, encryption, or tapes that wasn't included in the UPDATE.

[Aaron Sakovich]

Hi Hoff,

> Same SDLT tape drive for both operations?

As stated in the OP, there is only one system and only one tape drive in use.

> What particular SDLT media?

This is a very good question. I'm checking with the system operator to find out which specific media they are using. I know that they do have a stock of SDLT-1 tapes that have been used for both 220 and 320 drives.

This drive in particular is a 320.

>Please post the DCL commands used for the
>tape creation (including the INITIALIZE and
>the MOUNT), and the DCL commands used to
>(try to) access the contents.

As stated above, I've not even gotten to the point of trying to access the contents -- I'm simply trying to overwrite the tape. In addition to the Backup command quoted above, here are the init & mount commands:

Initialize Tape$SDLT: Backup /Media=Compact

Mount /foreign Tape$SDLT: Backup /Media=Compact /NoUnload

I'm awaiting for a response concerning which cartridge is being used, and for media to be loaded now to continue my tests.

[Shriniketan Bhagwat]

Hi,

Can you try the BACKUP with /IGNORE=LABEL qualifier instead of /LABEL=BACKUP

Regards,
Ketan

[Jur van der Burg]

I tried this with LD V9.3 and it works without a problem. It looks like there's a problem with the tape drive, tape cartridge or MKdriver. Is there anything in the error log?

Jur (LDdriver author).

[Jon Pinkley]

Aaron,

Hardware compression in the SDLT 320 should be transparent to what is written and read from the tape, but given you are using software encryption prior to sending the data to the tape drive, I see no benefit of asking the drive to compress the data.

Encrypted data appears to be random, and random data cannot be compressed.

You haven't stated one way or the other if this SDLT 320 drive has been used successfully without using encryption.

Another thing that shouldn't make a difference is having backup write the volume header. That can be accomplished by using the /REWIND switch on the first save set you write to the tape. I always do this, but that is because I also use /TAPE_EXPIRATION

So can you verify that the following works before introducing encryption into the mix?

$ init tape$sdlt: backup
$ mount/foreign/nounload tape$sdlt:
$ backup/image disk: tape$sdlt:backup.bck/save/label=backup/block=32768/REWIND
$ dismount/nounload tape$sdlt:
$ mount/foreign/nounload tape$sdlt:
$ backup/image disk: tape$sdlt:backup.bck/save/label=backup/block=32768/NOREWIND ! this should append a second backup.bck save set
$ dismount/nounload tape$sdlt:
$ mount/for/nounl tape$sdlt:
$ backup/list=backup.lis tape$sdlt:*.*/save
$ search backup.lis "save set:"

This should have two lines with BACKUP.BCK

If this works, then try the same using /encrypt

Jon

[Aaron Sakovich]

I've resolved the problem. The issue was NOT related to the /Encrypt switch.

The tapes in question had been used before, and not necessarily on a VMS system. The tapes may or may not have been used on an SDLT-320 drive, also.

I added the following switch to all the Init, Mount, and Backup commands:

/Density=SDLT320

I also added the following switch to the Backup command:

/Rewind

The backups are now correctly being written to tape.