[Info-vax] analyze/disk errors

[Stephen Hoffman]

On 2013-12-05 19:32:07 +0000, tadamsmar said:

> That's not what the VMS documentation says.  This thread is interesting 
> in that I have never once got advice here that just flat out 
> contradicts the documentation and yet it keeps happening in this 
> thread.  Also I did what the documentation said to do and nothing 
> happened that contradicted the documentation.

Either the documentation is wrong, or it's being misread.

>> Ask your friend backup to restore the "some other files".
> 
> Not sure what you mean. I restored all the files on the disk.

At US$30 a pop for decent 146 GB 10K SCSI disks (new), messing around 
with old disks that are tossing errors isn't worth the time.

> Here's what I get on the system in question:
> 
> $  copy dsa0:[000000]badblk.sys nla0:
> %COPY-E-READERR, error reading DSA0:[000000]BADBLK.SYS;1
> -RMS-F-RER, file read error
> -SYSTEM-F-ILLBLKNUM, illegal logical block number
> %COPY-W-NOTCMPLT, DSA0:[000000]BADBLK.SYS;1 not completely copied

Probably off the end of the disk.   It's a file you should not 
generally be directly accessing.  The file system and tools 
special-cases it, though it would appear ANALYZE /DISK isn't doing a 
stellar job of accessing it.


> Not sure what role badblk.sys has in a shadowset if any, but it's 
> certainly not the same role is plays on a non-shadow set disk.

It's where inaccessable blocks live.  End of the disk blocks.  
Sometimes reserved blocks.   With HBVS, bad blocks transiently.


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