Re: System problems - some progress

On Thu, 2011-03-24 at 18:20 -0500, Paul Hartman wrote:
> On Thu, Mar 24, 2011 at 5:33 PM, Lindsay Haisley <[email protected]> wrote:
> > Newer versions?  Kernel 2.6.36 has a config option for RAID autodetect.
> > What are you referring to here, mdadm?
> 
> Even the newest kernel supports autodetect, but autodetect only works
> with a specific kind of RAID superblock, I think version 0.90.
> Different versions of mdadm create arrays with different versions of
> superblock by default. Newer versions of superblocks cannot
> (presently) be autodetected by the kernel, so anyone using a newer
> type of superblock will have to do the "manual" config like this
> anyway.

Ah. So it follows that if the array was created with an earlier version
of mdadm, and mdadm -D tells me that the superblock is persistent and is
version 0.90 then autodetection should work.  It would also follow that
if I turn off RAID autodetection in the kernel, and spec'd ARRAYs by
UUID in /etc/mdadm.conf, I should be OK.

> As for why it's not working in your case, I really don't know, but
> hopefully you can at least get it working /somehow/ so that you can
> use your system normally to get real work done, and can investigate
> why auto-detect doesn't work the way you'd like it to with less
> urgency. 

If I can't, it's not the end of the world, since I can just let it be
and build up a new box and move stuff to it.  I need to emerge -u mdadm
since I'm currently at v2.6.8 and the portage tree recommends v3.1.4.  I
need to really make sure that this upgrade will work, since, unlike
udev-141, I can't back-version if the newer mdadm causes a problem.

> I've got an old Gentoo system that takes days to update, but
> if the system is usable during that time it's not really a big deal to
> me. It's the days-long updates when the system is in an unusable state
> that are a real nightmare.

Yeah, there's some brilliant programming in Gentoo, and I really like
the concept of what Duncan calls the "rolling upgrade" design
philosophy, but it's a slow and complex process.  I'd rather deal with a
fixed version distribution these days and let others deal with the
builds.

-- 
Lindsay Haisley       |  "We are all broken toasters, but we still
FMP Computer Services |    manage to make toast"
512-259-1190          |
http://www.fmp.com    |        - Cheryl Dehut
                      |