Re: disk non-destructive bad-block write/fix?

From: David Christensen <dpchrist_at_holgerdanske.com>
Date: Tue, 20 Sep 2022 19:00:33 UTC 
On 9/19/22 20:40, Gary Aitken wrote:
> I have a system I need to back up and my only available backup disk is
> throwing a lot of errors like:
> 
>    (da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 3c fd e5 68 00 00 40 00
>    (da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
>    (da0:umass-sim0:0:0:0): Retrying command
>    (da0:umass-sim0:0:0:0): WRITE(10). CDB: 2a 00 3c fd e6 68 00 00 20 00
>    (da0:umass-sim0:0:0:0): CAM status: CCB request completed with an error
> 
> Is there a way to exercise the free blocks on a ufs disk and move all
> defective ones to the bad-block list?
> 
> Or is that already happening in the above scenario?
> 
> The command was
>    find . | grep -iv -f ./backup_ignores.txt | cpio -pmd 
> /mnt/backup_20220919/
> 
> The disk is about 40% full but I'm wondering if the whole rest of it is
> trashed.


Buy a new backup disk and back up everything.  Better yet, buy more than 
one and rotate them.


For off-line back up disks, I find mobile racks to be more reliable than 
USB/ Firewire/ eSATA:

https://www.startech.com/en-us/hdd/drw150satbk


Zero-fill, test, and/or repair the old disk using the manufacturer 
diagnostic.  For example, Seagate:

https://www.seagate.com/support/downloads/seatools/


David