Re: [OSR-users] New Preview RPMs for next Release Candidate of comoonics-bootimage

[Marc G. <gr...@at...>]

On Tuesday 28 April 2009 02:13:41 Dan Magenheimer wrote:
> Hi Marc --
>
> Thanks for the reply.  First, let me clarify that I am
> trying two different approaches:
>
> (A) Use your entire OSR RHEL5+OCFS2 howto (with
>     a Xen-paravirtualized 2.6.29 kernel running as a
>     guest on Xen-3.4.0), or
> (B) Build my own initrd and use your OSR scripts
>     only after my initrd finishes.
>
> I couldn't get (A) to work... the initrd built using
> the howto was failing very early, so I decided to
> try with (B).  I hoped that (B) would be easier because
> your code is very general to handle many different
> kinds of systems, and mine could be much more specific.
>
> HOWEVER, I just discovered one problem with (A).
> Your mkinitrd process builds a huge (200MB) initrd
> and there appears to be a BUG IN XEN that fails
> to load large initrds (larger than about 100MB)!
>
> Your initrd is so large because my lib/modules/2.6.29
> is very large.  If I delete that from initrd built
> using the howto, the initrd.gz is only about 24MB
> and I am able to boot and see the ATIX logo and
> it drops into the rescue shell (because I haven't
> specified the MAC-Addresses I think).  However other
> boot errors complain about modules that are missing.
> I will try to build a kernel with fewer modules and
> see how that goes.
You could also call mkinitrd with the -l/-L option. This will build a minimal 
initrd also only from loaded or specified modules. See mkinitrd -h.
>
> Other feedback:
>
> I wonder if your script detecting "distribution"
> and "shortdistribution" are correct for all versions
> of RHEL and Oracle Enterprise Linux?  I am getting
> "unknown" for both (from listparameters in the rescue
> shell), though I am booting Oracle Enterprise Linux 5
> update 2.
I didn't test it for Oracle EL5 and I would bet it does not work. Could you 
send me the contents of /etc/redhat-release or is it /etc/oracle-release?
Then I build a patch to also support OEL5.
>
> I also see that your test for detecting xen in xen-lib.sh
> is not very good.  You may want to test for /proc/xen
> instead of (or in addition to) /etc/xen.
/etc/xen should only be tested for Dom0 "NOT" DomU.
DomU detection => xen_domx_detect
Dom0 detection => xen_dom0_detect
in etc/xen-lib.sh
>
> And why when "Loading modules for all found network cards"
> do I get "FATAL: Module xennet not found"?  I have xen
> networking compiled into my kernel so there is no module
> for it.  Should this be fatal?
Hm. Up to now it seems to be ;-) . Nowerdays I only saw kernels which are 
modularized. So this is a usecase where the errordetection detects a 
nonexistant error. I'll have to think about it. As a workaround you could add 
a xennet off to /etc/modprobe.conf.

At least I would suppose it to work.
>
> > Ok. But still we need the mac adress for detecting the nodes
> > identity in the /etc/cluster/cluster.conf.
>
> Is that really necessary?  Ocfs2 only requires the
> node name, not the mac address.  But I guess I can
> configure the mac address in the xen guest config file
> so I can live with this.
Yes this still is necessary. We are going to make it more flexible in future 
versions. Up to now that's the only way. Sorry about this.
>
> Thanks,
> Dan

You're welcome
Marc.

-- 
Gruss / Regards,

Marc Grimme
http://www.atix.de/               http://www.open-sharedroot.org/