[linux-lvm] How to extend a root LVM volume?

[Mark Miksis <mark.nospamplease@miksis.com>]

I'm trying to extend a root LVM.  I'm using LVM2 on FC2.  Here is what
I've tried:

I ran lvextend when the system was booted normally and the volumes were
mounted.  This worked as expected and lvdisplay properly shows the new
larger size.

Then I booted into the FC2 rescue CD and instructed it to NOT search for
and mount Fedora installations.  I then ran:
# resize2fs /dev/Volume00/LogVol00
I don't have the specific error, but it basically says that the
specified volume doesn't exist.  Indeed if I look in /dev, my volume
group and volumes are nowhere to be found.

At that point I tried:
# lvm
lvm> vgscan
After only about 1 second, it responds that no volumes are found.

I also tried rebooting from the CD and letting it mount my
installations.  In this case, the volume and volume groups are properly
discovered and mounted.  However, if I try to unmount the volume, it
always responds with "device busy".

Is this a problem with how the FC2 rescue disk scans for volumes?  Any
help would be appreciated.