kern/43629: RAIDframe should be able to ignore read errors while replacing a component

[tron%zhadum.org.uk@localhost]

>Number:         43629
>Category:       kern
>Synopsis:       RAIDframe should be able to ignore read errors while replacing 
>a component
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    kern-bug-people
>State:          open
>Class:          change-request
>Submitter-Id:   net
>Arrival-Date:   Sat Jul 17 10:40:01 +0000 2010
>Originator:     Matthias Scheler
>Release:        NetBSD 5.1_RC3
>Organization:
Matthias Scheler                                  http://zhadum.org.uk/
>Environment:
        
        
System: NetBSD colwyn.zhadum.org.uk 5.1_RC3 NetBSD 5.1_RC3 (COLWYN.64) #1: Thu 
Jul 1 23:21:22 BST 2010 
tron%colwyn.zhadum.org.uk@localhost:/src/sys/compile/COLWYN.64 amd64
Architecture: x86_64
Machine: amd64
>Description:
Both disks in the primary RAIDframe RAID 1 volume of my server developed
bad blocks this week (in a single nighty :-( ). RAIDframe dropped one
disk out of the RAID 1 and I'm not stuck with the remaining disk that
has bad blocks as well.

I've just added a replacement disk to my server and it would be really
nice if I could use something like "raidctl -R -f /dev/wd0a raid0" to
force RAIDframe to add that disk to the RAID 1. This would allow me to
migrate the data to the new disk seamlessly. I don't care about the
blocks on the old disk which cannot be read as they are lost anyway.

>How-To-Repeat:
Try to add a new disk to RAID 1 volume with only one disk left which has
bad sectors.

>Fix:
None provided.