DDS4 tape compression

[Dan Garthwaite]

Hey guys, some oddities with my DDS4 drive.

1) vxdump is failing at 20.1 gigs of data on a dds4 tape.

2) lssf /dev/rmt/1m reveals best compression available

3) the data is compressable

4) I had to rmsf /dev/rmt/1m* AND /dev/rmt/c3*, because doing one, and not the other, resulted in mksf recreating the old tape driver ( the file's date showed something from years ago ) Between the rmsf and mksf, the file did not appear in a ls listing

5) strangest of all: I downloaded and compiled Eric Lee Green's excellent scsi tape info/manip program, and it reports the following ( with a DDS4 tape in drive )


Product Type: Tape Drive
Vendor ID: 'HP '
Product ID: 'C5683A '
Revision: 'C908'
Attached Changer: No
SerialNumber: ''
MinBlock:1
MaxBlock:16777215
Ready: yes
BufferedMode: yes
Medium Type: Not Loaded
Density Code: 0x26
BlockSize: 0
DataCompEnabled: no
DataCompCapable: yes
DataDeCompEnabled: yes
CompType: 0x20
DeCompType: 0x0
BOP: yes
Block Position: 0


Note the DatacompEnabled, also note the MediumType. Curious.

6) It's not the jumpers. b)

Any feedback on any points is greatly appreciated. This place has a reputation of being the damned finest support forum, and you've helped me out before. Thanks.

-Dan Garthwaite
Science Applications
International Corporation

[Volker Borowski]

Sounds to be patchable.

You have PHKL_20530 (on 11.00) or superseeded installed ?

http://europe-support2.external.hp.com/wpsl/bin/doc.pl/sid=8fbc68f10ff6b2ce02/screen=wpslDisplayPatch?HW=s800&OS=11.00&PACH_NAM=PHKL_20530

http://europe-support2.external.hp.com/wpsl/bin/doc.pl/screen=wpslDisplayPatch/sid=ec33056a14032abc72?PACH_NAM=PHKL_24221&HW=s800&OS=11.00

If the tape has been replaced on the same SCSI adress, where an older tape has been before, it might be possible, that only the devicefile, but not the driver has been updated ?!?
I had no DDS4 since yet, but it might be, that it requires a tape2 driver instead of tape ?

Suggest you post your "ioscan -fn" and "lssf", may be someone with a working DDS4 can tell you, if kernel driver and major/minor numbers of the device file are ok.

Volker

[Gregory Fruth]

I have an HP SureStore DAT40 DDS-4 (HP C5683A) working
in my J2240 under HP-UX 10.20. The driver is "stape", though it
might be different on servers (the J2240 is a workstation). Here's
some info for you to compare:

From "ioscan -fn":

Class I H/W Path Driver S/W State H/W Type Description
==============================================================================
target 1 8/0/4/0.3 tgt CLAIMED DEVICE
tape 1 8/0/4/0.3.0 stape CLAIMED DEVICE HP C5683A
/dev/rmt/1m /dev/rmt/1mn /dev/rmt/c3t3d0BEST /dev/rmt/c3t3d0BESTn
/dev/rmt/1mb /dev/rmt/1mnb /dev/rmt/c3t3d0BESTb /dev/rmt/c3t3d0BESTnb

From "ls -l":

crw-rw-rw- 2 bin bin 205 0x033000 Jan 16 01:01 /dev/rmt/1m
crw-rw-rw- 2 bin bin 205 0x033080 Apr 3 2001 /dev/rmt/1mb
crw-rw-rw- 2 bin bin 205 0x033040 Apr 3 2001 /dev/rmt/1mn
crw-rw-rw- 2 bin bin 205 0x0330c0 Apr 3 2001 /dev/rmt/1mnb
crw-rw-rw- 2 bin bin 205 0x033000 Jan 16 01:01 /dev/rmt/c3t3d0BEST
crw-rw-rw- 2 bin bin 205 0x033080 Apr 3 2001 /dev/rmt/c3t3d0BESTb
crw-rw-rw- 2 bin bin 205 0x033040 Apr 3 2001 /dev/rmt/c3t3d0BESTn
crw-rw-rw- 2 bin bin 205 0x0330c0 Apr 3 2001 /dev/rmt/c3t3d0BESTnb

[Gregory Fruth]

Here are the relevant bits from my swlist:

700QPK1020 ACE.200009.01 Workstation Quality Pack for HP-UX 10.20 (September 2000)
B3782EA B.10.20 HP-UX Media Kit (Reference Only. See Description)
B6193EA ACE.199912.01 Workstation ACE for HP-UX 10.20 (December 1999)
B6378DA ACE.199912.01 Networking ACE for HP-UX 10.20 (December 1999)
HPUXEngCR700 B.10.20 English HP-UX CDE Runtime Environment
XSW700GR1020 B.10.20.50.3 General Release Patches for HP-UX 10.20 Workstations (Sept. 2000)

My drive is successfully backing up 24 GB of data
per tape, so the compression must be working properly.

HTH