LVM and ext3 FS labels not playing nice?

[James Puellmann]

This applies to RHEL ES 3.0 running on Dell PowerEdge machines.

All of our ext3 filesystems (except /boot) are on logical voumes.

As a general rule, I like to use FS labels whenever possible, just to 
avoid confusion. I don't want to remember which LV is /var; I just want 
to know it's the one with LABEL=/var. So I replaced all of the 
/dev/vg##/lvol## entries in my /etc/fstab file with LABEL=<whatever>. So 
far, no problems. The system will boot like this.

The problem happens  after I upgrade the kernel. After upgrading the 
kernel, the kernel panics at boot time because it can't find the initrd 
image.

After rescuing the system, rewriting the fstab so it no longer uses 
LABELs, and manually running mkinitrd for the new kernel, everything is 
back to normal. hrm.

So it seems that using LABEL entries for logical volumes in fstab causes 
mkinitrd to create a broken img file (though it doesn't error out). 
Replacing the LABEL entries with /dev/vg##/lvol## and rerunning mkinitrd 
fixes this problem.

Can somebody shed some light on what exactly went wrong here? I've had 
success running mkinitrd with LABEL entries before I was using LVM but 
it apears that LVM + FS labels + mkinitrd = kernel panic. What's broken 
and how do I fix it?

- James Puellmann
:wq