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Published 20 hours ago • verified publisher icon markh794

Add support in VHF to indicate whether or not drive needs to be cleaned

Open rohr22 opened this issue 1 year ago • 8 comments

Hi, Mark.

Can mhvtl be updated so that the very high frequency (VHF) data which indicates whether a drive needs to be cleaned or not could be added? Our application is logging a debug message which indicates we cannot get the VHF data to check the clean state. It would be nice if mhvtl supported the clean state, so we don't see this debug log message.

Thank you, Peter

rohr22 avatar Jul 17 '23 20:07 rohr22

Hi Peter, Just looking at the IBM Ultrium specs for the VHF now. What a useful log page. Some of the fields may require a little thought on how to integrate correctly - especially the Device Activity field. The medium present / medium seated bits should be quite simple. As should the CRQST & QRQRD.

Thank you for highlighting this log page. Now to find "spare" time to implement :)

Cheers Mark

markh794 avatar Jul 17 '23 21:07 markh794

Hi, Mark. Any news on updating MHVTL to handle this situation? We are seeing a lot of debug messages related to this when we use IBM LTO-6 tape drives with MHVTL.

rohr22 avatar Apr 25 '24 16:04 rohr22

Hey Peter, Thanks for the prompt. To be honest, I've forgotten about this - just being busy with work and general life stuff. Let me re-visit this.

markh794 avatar Apr 26 '24 00:04 markh794

Hello Peter, thanks for hanging in there. I've now added basic support for Log Page 0x11 - VHF Currently, only for the IBM Ultrium LTO3 and above emulations. Please let me know if it works for you and what bits of the documentation I've misinterpreted :)

markh794 avatar May 01 '24 02:05 markh794

Hi, Mark. Thank you very much. We will give this a try and let you know how it works.

rohr22 avatar May 01 '24 03:05 rohr22

With VERBOSE=3 in the /etc/mhvtl.conf file, I noticed messages like this are getting logged almost constantly:

May 2 12:04:13 testtwox86-rh9 /usr/bin/vtltape[112187]: lookup_log_pg(): Looking for: log page 0x11 May 2 12:04:13 testtwox86-rh9 /usr/bin/vtltape[112187]: lookup_log_pg(): Device Status (0x11) May 2 12:04:13 testtwox86-rh9 /usr/bin/vtltape[112184]: lookup_log_pg(): Looking for: log page 0x11 May 2 12:04:13 testtwox86-rh9 /usr/bin/vtltape[112184]: lookup_log_pg(): Device Status (0x11)

grep -c "lookup_log_pg" /var/log/messages 1707020

Previously, I didn't see stuff getting that logged from vtl when using VERBOSE=3. Is the logging too verbose now?

rohr22 avatar May 02 '24 17:05 rohr22

Thanks for the bug report. Although harmless, it was annoying. A fix 8a88fa87861411e46782dd711e3be5a7c4bbbbbb has been applied

markh794 avatar May 03 '24 00:05 markh794

Just to state the obvious. Verbosity above 1 does impact the performance (thoughput)

markh794 avatar May 05 '24 00:05 markh794