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HP OpenVMS Systemsask the wizard |
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The Question is:
Dear Wizard,
We have AS2100 4/200 (OVMS 6.2) and raid array (level 1) based on SWXCR-EA
card (RCU v3.3). Disks in raid set are RZ28. One day SWXCR monitor started
to produce following messages:
SWXCR-DRA: The hard disk at channel 0 target 2 has <n> soft errors
where <n> was varying from time to time. Finally the very errors (I think
so) forced one page in our production DB to become corrupted. This story
finished successfully: suspicious disk was replaced and DB was recovered.
But I have some questions:
What "soft error" means ? If these errors relates with some type of
media
error, then why bad block list was empty? Also I didn't find any relevant
entries in ERRLOG.SYS. And another interesting thing: I checked
suspicios disk what was extracted from raid set with
ANALYZE/MEDIA/EXERCIZE=(FULL)/SHOW=(BEFORE,AFTER) and found no one error.
Is there any place in VMS where I can find more detailed info about
these
errors: type of error, LBN it encountered in ?
Is it possible that one errorneous drive in raid level 1 logical disk
causes data to be corrupted?
Thank you.
Valentin Likoum
ncc_valent@my-dejanews.com
The Answer is : Please contact your hardware support organization or the SWXCR Wizard, this is well outside the area of the OpenVMS Wizard. Most disk devices present the appearance of no bad blocks, much of the bad block support in OpenVMS dates back to the time prior to controllers and low-level drivers with support for revectoring bad blocks. Depending on the particular controller implementation and configuration, bad block detection occurs on reads, and revectoring may occur only when the block is rewritten, though some controllers will detect impending failure and revector the block without host involvement. Traditional host-based bad block detection and revectoring typically requires the contents of the block to be rewritten before the bad block is retired.
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