DLm0569E, DLm0595E: Attempting to Update a DLm Write Once Read Many Tapes

DLm0565E and DLm0569E error messages issued upon attempting to update a Write Once Read Many (WORM) tapes. 

09/01/2021 05:34:50 DLM1 VT: DLm0500I: Scratch of volume 140664 requested by host via device 51FF, dsn='.SYSBKUP.G6728XYZ'
09/01/2021 05:34:50 DLM1 VT: DLm0501I: Volume 140664 (/tapelibPRD/DD1_P1_FS1/140664) scratched and erased
09/01/2021 11:42:00 DLM1 VT: DLm0440I: Device 5100 Scratch volume 140664 (/tapelibPRD/DD1_P1_FS1/140664) mounted
09/01/2021 11:42:00 DLM1 VT: DLm0405I: Device 5100 Display: ' 140664S'
09/01/2021 11:53:28 DLM1 VT: DLm0593I: Device 5100 volume 140664 (/tapelibPRD/DD1_P1_FS1/140664) set expiration: 2021/09/02 00:53:28
09/01/2021 11:53:28 DLM1 VT: DLm0280I: Device 5100 volume 140664 AMDD skipped 1845743 too-small blocks
09/01/2021 11:53:28 DLM1 VT: DLm0490I: Device 5100 volume 140664 unloaded
09/01/2021 11:53:28 DLM1 VT: DLm0405I: Device 5100 Display: 'R140664 '
09/01/2021 11:53:28 DLM1 VT: DLm0405I: Device 5100 Display: 'R140664 ' 'MMEDIA2S' (blink) (alternating)
09/01/2021 11:53:57 DLM1 VT: DLm0405I: Device 5100 Display: 'R139144 ' 'M140664S' (blink) (alternating)
09/01/2021 11:54:00 DLM1 VT: DLm0440I: Device 5100 Volume 140664 (/tapelibPRD/DD1_P1_FS1/140664) mounted (Modifiable)
09/01/2021 11:54:00 DLM1 VT: DLm0405I: Device 5100 Display: ' 140664S'
09/01/2021 12:07:21 DLM1 VT: DLm0490I: Device 5100 volume 140664 unloaded
09/01/2021 12:07:21 DLM1 VT: DLm0405I: Device 5100 Display: 'R140664 '
09/01/2021 12:07:21 DLM1 VT: DLm0405I: Device 5100 Display: 'R140664 ' 'M139144S' (blink) (alternating)
09/01/2021 12:07:53 DLM1 VT: DLm0405I: Device 5100 Display: 'R139144 ' 'M140664S' (blink) (alternating)
09/01/2021 12:07:57 DLM1 VT: DLm0440I: Device 5100 Volume 140664 (/tapelibPRD/DD1_P1_FS1/140664) mounted (Modifiable)
09/01/2021 12:07:57 DLM1 VT: DLm0405I: Device 5100 Display: ' 140664S'
09/01/2021 12:07:57 DLM1 VT: DLm0565E: Device 5100 Illegal volume mod attempt, volume 140664, offset 0, block 0 (TM)
09/01/2021 12:07:57 DLM1 VT: DLm0569E: Device 5100 Error extending volume 140664
09/01/2021 12:07:58 DLM1 VT: DLm0490I: Device 5100 volume 140664 unloaded

DLm "WORM" tapes are restrictive in both what updates can be made and how they can be made. In the sequence above, tape 140664 is scratched, then mounted and written to. Not long after, it is mounted again, modifiable, successfully. It is mounted modifiable again and in the last mount sequence shown above, the type of update is failed.

"The host can only write to a modifiable WORM tape at the end of the last dataset (between the last data block and the tapemark preceding the trailer labels), or between two tapemarks at the end of the existing volume. This corresponds to the host appending to a dataset (writing with DISP=MOD) or adding a new file to the tape. Attempts to write at any other location results in a unit check with sense of command reject, ERPA code x'30'."

The unit is working as designed as this is an unpermitted update attempt to a WORM tape.

DLm0569E:

Device <devicename> error extending volume <volser>
  Description: An error occurred during an attempt to write to (modify) a
     previously locked virtual tape volume on a WORM filesystem. This message
     should be preceded by one or more messages that explain the problem(s)
     encountered.
  System Action: The Host write command is rejected with a Unit Check.

DLm0565E:

Device <devicename> Illegal volume mod attempt, volume <volser>, offset <nnnnnn>, block <nnn>
Description: An attempt was made to write to (modify) a previously locked
virtual tape volume on a WORM filesystem, at a location other than at the end
of the existing data. Once a virtual tape volume is locked on a WORM filesystem,
you can append to the dataset but you cannot modify it in any other way.
System Action: The Host write command is rejected with a Unit Check.
User Action: Correct the Host job or application so that it does not
try to write anywhere but at the end of the existing data.

This information is found in the User Guide for DLm8500 with Data Domain, Isilon, PowerScale, and Cloud, Chapter 8 WORM Tapes.