Thanks for the reply Stijn,
 
I've attempted an inird rebuild as suggested - alas no difference. I've
also tried rolling-out the kernel-rt rpm and reinstalling. 

The full kernel panic message is:
--------------------------------------------------------
dracut Warning: Signal caught!
dracut Warning: LVM vg_minibeast/lv_root not found
dracut Warning: LVM vg_minibeast/lv_swap not found
dracut Warning: Boot has failed. To debug this issue add "rdshell" to
the kernel command line
Kernel panic - not syncing: attempted to kill init!
Pid: 1, comm: init Not tainted 2.6.33.9-rt31.75.el6rt.x86_64 #1
--------------------------------------------------------

Having used rdshell to check things out, the hard drives just aren't
present under /dev/ - no LVM/VolGroup/etc - nothing which would suggest
a drive. 

As I said, we've had three systems go down with this problem, all at
different points. However, all three share similar architecture - for
example, all support firmware-RAID (Intel Matrix Storage Manager). All
are built to the same standard, in the following order:
- SL6.1 64bit
- selinux disabled
- software updated
- latest kernel-rt installed from slc website  

Dell R5500:

RAID1 (Mirror) HDD configuration. Initially installed and working fine,
then dracut threw on both RT and non-RT kernels. However, we had a RAID
freak-out immediately before this panic, AND software updates were
enabled. We've done a full rebuild back to standard and everything is
working fine again (including kernel-rt).

Dell R5400:

RAID1 (Mirror). Inititally installed and working fine, then kernel panic
on RT kernel only. Software updates were active and may have updated the
kernel before the panic. 

Dell T5500: 

No RAID enabled (although still present in firmware). This was a fresh
install last week with kernel-rt throwing up immediately upon
installation.


I think its fair to say *something* is causing this, my guess being one
of the following:
- the latest kernel-rt package may be dodgy.
- the Intel Matrix Storage Manager may be reconfiguring on-the-fly
somehow (although its impossible to get log access unless Windows is
installed)
- theres a timing glitch between kernel-rt and dracut which is throwing
random faults.

Any suggestions very welcome. The only good idea I've had is to try and
update dracut to version 007 (its at 004 by default) - however I'm still
struggling to get proper info on this and how to do it.

Mat



-----Original Message-----
From: Stijn De Weirdt [mailto:[log in to unmask]] 
Sent: 17 October 2011 10:25
To: Mathew Maher
Cc: [log in to unmask]
Subject: Re: SL6.1 MRG/realtime patch - good and bad news

> All three are panicing over the same error: "*dracut*" throwing errors

> and warnings, mainly about not finding the swap volumes. I will print 
> some proper error messages later, if anyones interested, but at the 
> moment it's friday afternoon, packing up time, and I've got a beer 
> waiting for me.
> Would be interested in anyone shedding light of exactly what "dracut"
> is, not one I've ever come across before. Of course, if anyones got 
> any ideas what might be going on, all comments greatly received!
when you installed the kernel rpms, something must have gone wrong when
building the kernel initrd images. you should verify that all went fine.

otherwise, you could try to rebuild the initrd files with
/sbin/new-kernel-pkg --package kernel --mkinitrd --depmod --make-default
--install <rtkernelname>



stijn

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