[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Questions about software RAID level 1 (how long should it take to sync, etc?)



This one time, at band camp, Mike Garey said:
> On 4/4/06, Stephen Gran <sgran@debian.org> wrote:
> > This one time, at band camp, Mike Garey said:
> > > ALERT! /dev/md0 does not exist.  Dropping to a shell!
> >
> > My first advice is just to wait at that prompt for a few minutes, and
> > then look in /dev.  It can take a little while for the device node to be
> > created, and the scripts aren't that smart about it.  There has been
> > some discussion about sleeping until md0 is created or some time limit
> > expires, whichever comes first, but I haven't seen that implemented yet.
> 
> After the prompt,  it drops me right into a busybox shell, and
> /dev/md0 is never created (I've left the box on for the past hour or
> so and nothing).  What is it exactly that tells md to create a
> /dev/md0?  Or is this something that should automatically happen, as
> long as the md module is loaded?  And what is required to be able to
> mount a hard drive on /dev/md0? Does the device type of the drive need
> to be FD, or can it still be 83 (linux)?  Thanks,

That's decidedly odd.  What should happen is that the module for the md
array is loaded by the kernel when it tries to find the root filesystem.
After some module magic, a sysfs event happens, and then udev creates
the device node.  I have never heard of it taking more than a couple of
minutes for this series of events to happen.  Something is seriously
wierd on your end - do you have the module for the md array in the
initrd?  Is the approriate udev magic in the initrd?  If not, can you
modporbe the necessary modules from busybox, and get an md0 device?  Can
you MAKEDEV it?

Just some thoughts,
-- 
 -----------------------------------------------------------------
|   ,''`.                                            Stephen Gran |
|  : :' :                                        sgran@debian.org |
|  `. `'                        Debian user, admin, and developer |
|    `-                                     http://www.debian.org |
 -----------------------------------------------------------------

Attachment: signature.asc
Description: Digital signature


Reply to: