Re: [linux-lvm] Cannot get rid of root filesystem LVM snapshot

[Alasdair G Kergon <agk redhat com>]

The tools do not support root snapshots properly yet - whether or not they
work is down to chance.  To remove one reliably you need lvremove from a
rescue environment - you're lucky lvremove is refusing to proceed - if it
got further it could hang your machine.  In principle you can recover
without rebooting but you'll need to write a custom script to run various
dmsetup commands from a ramdisk, for example, and then fix up the lvm2
metadata with activation disabled.  [If you learn how snapshots are
created/destroyed you can work out what to do: sorry, it's too much for me
to explain here.  This is what the tools will want enhancing to do to
provide proper support.]

Older kernels like yours however can get into a state where recovery is only
possible by writing directly to kernel memory, if you already ran certain
commands in the wrong sequence.

Alasdair
-- 
agk redhat com