C5686A DDS4 on s700 10.20 system

[Garret Straub]

I am trying to set up a DDS4 C5686A drive to run externally on a 10.20 workstation and have loaded patch PHKL_20528 on the system as of late. The drive shows claimed, the 'stape' driver is in the kernel, but I am not able to perform a backup to the device. What am I missing with and how do I get the device working? I am also having trouble with a Sony Optical drive, any recommendations for this device would be appreciated as well.

thank you,
G

[Steven E. Protter]

Shalom,

I believe that hardware was invented after the OS was frozen and pegged for non-support.

I think you will not get this device working unless HP releases drivers for the OS and I doubt that is going to happen.

If in fact the device is supported, I suggest you check for SCSI conflict and see if it shows up in cstm/mstm/xstm

SEP

[Michael Steele_2]

Insert a tape and using the 'mt' command see if you can forward and reverse. Use ioscan -funC tape to display the device files, ie, /dev/rmt/0m, /dev/rmt/0mn (no rewind).

# mt -t /dev/rmt/0m stat (* tape status*)

# mt -t /dev/rmt/0m -fsf 1 (* forward on record no rewind *)

# mt -t /dev/rmt/0mn -rew

Paste in the ioscan and the workstation model.

# model

[Bill Hassell]

10.20 is very, very old in OS version years -- obsolete since 2001. The DDS4 did not exist when 10.20 went out of support so it is no surprise that it does not work. The way to make it work is to install the latest version of HP-UX (11.11 or 11.23). But before you go to that trouble, your workstation may be too slow to keep up with the tape. Unlike newer tape drives that can slow down, the DDS4 and DDS5 drives require a minimum of 3 Mbytes/sec of continuous data or 6 to 10 Mbyte/sec if you select the compression driver option. For the DDS drives, data starvation causes a complete stop, a backspace and then a restart, about 3-5 seconds of zero bytes/sec. You could see 100:1 to 500:1 degradation in performance if your backup program, CPU speed and disks are not fast enough.

Most decisions for newer drives are are made to reduce the number of tapes (ie, fit everything on one tape) but virtually all tape drives with higher capacity need higher data rates too. A DDS3 changer is probably the better choice as well as using fbackup or possibly HP Omniback so that tape changing can be automated.

[Andrew Rutter]

hi,

I seem to remember coming across this before.

Im pretty sure there was a cumlative sam patch also that came out to add support for the drive. this was needed so fbackup and such like could work with the drive.

Check if you have this patch installed
PHCO_22268

details here
http://www5.itrc.hp.com/service/cki/patchDocDisplay.do?patchId=PHCO_22268

has reference to the dds4 drives and adding support

Andy