My box lost one of its raid 5 drives the other day. When I rebooted, I
found that I couldn't mount my root filesystem because of that missing
drive, even though it should have happily assembled in degraded
mode. I had to boot from a rescue disk and reassemble the drive from
there (which took hours).
It would have been much more friendly of the initrd to allow the md
device to assemble in degraded mode. I don't think it would be any
less safe either.
So I vote heartily to add --run to the yaird mdadm template. Patch
attached for your convenience.
--- Templates.cfg 2006-05-28 14:14:29.000000000 -0700
+++ Templates.cfg.new 2006-05-29 17:38:55.000000000 -0700
@@ -315,7 +315,7 @@
SCRIPT "/init"
BEGIN
!mknod <TMPL_VAR NAME=target> b <TMPL_VAR NAME=major>
<TMPL_VAR NAME=minor>
- !mdadm --assemble <TMPL_VAR NAME=target> --uuid
<TMPL_VAR NAME=uuid> \
+ !mdadm --assemble <TMPL_VAR NAME=target> --run --uuid
<TMPL_VAR NAME=uuid> \
! <TMPL_LOOP NAME=components> <TMPL_VAR
NAME=dev></TMPL_LOOP>
END SCRIPT
END TEMPLATE
