Dat 24/6e Re-calibration / Compression Question

[Stefan Zientek]

Hi,

I've got a SureStore DAT 24x6 Autoloader, attached to a Windows2000 Server, which I use for backup with Yosemite's TapeWare package (6.3 SP1C).

Recently I noticed my backups were using more tapes than usual. On investigation I found that the DC symbol, which denotes Hardware Compression is enabled, was not visible, yet the device switches were set to enable it. After a power on cycle the Hardware Compression is shown as enabled again. However, this does not seem to stay set for long...

My first question is: is it possible that TapeWare can be switching off Hardware Compression, or is it possible that the drive is at fault?

Also, having run the TapeTools (Version 2,7 SR4) program I am advised that the drive might need re-calibrating and that there have been three errors at some point: F4, 84 and F4.

Having had calibration problems with earlier drives, for which this drive is a replacement under my ServicePack agreement, I tried to run the re-calibration script. This failed with the transcript and log shown below.

So my second and third questions are: what does this mean and what should I consider doing about it?

Is it something to do with Windows 2000 setup or again the drive?

All help appreciated!

Best regards,
Stefan Zientek


Script Output

HW-CONF = 0x00040003
Checking firmware file ../Firmware/C1557A_U812.frm correct ...
Storing values from drive calibration table
Write Current values DDS3: 0x28
Write Current values DDS2: 0x23
Reading tape usage from serial EEprom
Tape usage is dds2 = 0 dds3 = 911
Prompt user to load caddy with tapes
Waiting for caddy to load ...
Checking caddy contents ...
Loading tape from caddy slot 1
Checking for correct cartridge type ...
Using NEW media to Clean heads ...
Sending Servo Cmd : 18
Rewinding tape ...
Starting Write Current Recalibration ...
Checking for correct cartridge type ...
Set Buffered Mode: ON ...
Setting write current to 0x28 ..

Script Execution Log

Running script
- Reading script file C:\Program Files\HP Library & Tape Tools\scripts\ddsWriteRecal.ssc
Starting script execution of script DDSWriteRecalProc
Script exception occurred
Script exception occurred
I/O Exception (Error: 2048 - I/O: An unexpected Win32 error has been reported)
SCSI Cmd I/O at 2/0.5.0: Write Buffer

(Details from Explanation popup on entry)
Device: 2/0.5.0
Command: SCSI Cmd I/O at 2/0.5.0: Write Buffer
Data Phase: Data Out (Host -> Device) of 1 Bytes
Duration: 0 s
CDB: 3B 01 01 81 00 74 00 00 01 00
Data: 00000000: 28 [( ]

SCSIScript: auto abort triggered (Line: 743, Error: Auto abort triggered)
I/O Exception (Error: 2048 - I/O: An unexpected Win32 error has been reported)
SCSI Cmd I/O at 2/0.5.0: Write Buffer

(Details from Explanation popup on entry)
Device: 2/0.5.0
Command: SCSI Cmd I/O at 2/0.5.0: Write Buffer
Data Phase: Data Out (Host -> Device) of 1 Bytes
Duration: 0 s
CDB: 3B 01 01 81 00 74 00 00 01 00
Data: 00000000: 28 [( ]

Script execution completed

[David Ruska]

I don't have a quick answer for your compression problem. However, since you already have L&TT installed, you can run the drive compression test, which will verify the drive's ability to enable compression, and compress data.

Regarding the recalibration problem, the error you received (An unexpected Win32 error...) is a bug in the win2000 miniport driver. You can work around this problem by installing an older version of L&TT (2.7 SR3b) which allows the WINASPI driver to be installed (as a selection in the install process). You can then run L&TT and select the 'ASPI' I/O mode on the splash screen. The older version of LTT can be downloaded from: http://www.hp.hp.com/support/tapetools, and then click on 'download previous version' link.

(Note: for future versions of LTT we are currently testing a new ASPI version for win2k/XP.)

[Stefan Zientek]

Hi David,

Thank you for your information regarding using the previous version of TapeTools. Sorry to take so long acknowledging your reply, but I have been on leave for a week.

I used the earlier version and it suggested that I did not need to recalibrate my drive as it was set to optimum values.

I am still stuck with the issue as to whether it is possible for software to turn off the HC capability of the drive. Having power cycled the drive the condition is enabled (I see the HC), but after a run of TapeWare, where I tell it not to do any compression but to leave it to the drive, I find the state is changed (the HC is not visible). More help on whether this could be software or firmware would bew appreciated.

Can I add another question?

Does anyone have a list of the error codes for this type of autoloader - e.g. what do error codes F4 and 84 really mean and what can I do about them? I am finding that TapeWare is now reporting errors 1302 and 1319 (it's codes) which it variously describes as: 'Warning - Hard Error' and 'Critical - Clean Now' (which I've done up to ten times very recently), and would like to find out where the problem lies.

Many thanks again for any help or advice.

Stefan

[Stefan Zientek]

Hi,

For those looking here in the future, I have found a new option in my version of TapeWare that allows a job to specify that Hardware Compression is not to be used even if enabled. As I have both switches 1 and 2 set to on (viz. respectively, Hardware Compression enabled by default and it is possible to set/reset this by software). I assume that if I disabled switch 2, then the job would still use Hardware Compression.

Any further help on the error codes would be appreciated. I resorted to calling HP support on Friday morning (as I have a support pack) - still waiting for them to call back after initial collection of details...

Cheers, Stefan

[David Ruska · Accepted solution]

> Does anyone have a list of the error codes for this type of autoloader - e.g. what do error codes F4 and 84 really mean and what can I do about them?

Error code F4 - A cleaning sequence has occurred. (This is an informational message).

Error code 84 - The RAW retry limit has been exceeded for a group. (This results in a 'medium error' being reported to the host).

If the drive has been adequately cleaned, then the error 84 implies either a media problem (try a new tape), or the drive has lost R/W margin.

[Stefan Zientek]

David,

Thanks again for the information.

I used new, unused media, and cleaned the drive about 10 times before a recent job that still reported these errors. I've spoken to HP support today and they're going to replace the drive for similar reasons to those you provided.

Cheers, Stefan