Ubuntu

evms snapshots not surviving reboot

Asked by Luke Andrew

I've moved my Ubuntu install over to a evms based setup as follows:

hda3 + sda -> LVM2 Container -> LVM2 Region -> root volume with Reiserfs

This all works fine, I can create snapshots, mount them and generally
mess with them. However, the snapshots dont survive a reboot.

The main reason I moved to evms/lvm was so I could create snapshots of
my root filesystem, boot from the snapshot and test things that may
screw things up (like a dapper->edgy dist-upgrade )

I was under the impression that snapshots are persistent by default. Am
I wrong or is there something else at work here? Is it ok to use LVM2
regions for snapshots?

Cheers,
    Luke

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Luke Andrew (luke.andrew) said : 		#1

some version numbers:

Ubuntu - 6.06
evms - 2.5.4-5ubuntu6
LVM2 - 2.02.02-1ubuntu1.2

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Launchpad Janitor (janitor) said : 		#2

This question was expired because it remained in the 'Open' state without activity for the last 15 days.

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Luke Andrew (luke.andrew) said : 		#3

(possibly) Answering my own question in case anyones interested:

I've switched to straight LVM2 as EVMS is no longer supported in gutsy. I made the switch while running feisty, and still could not get persistent snapshots to work. To fix it, I added dm-snapshot, dm-mirror and dm-mod to /etc/initramfs-tools/modules and ran update-initramfs -u. This ensures that these modules are present in the /boot/initrd.img-x.xx.xx-xx-xxx image and loaded in early userspace, before any file systems are mounted, thus ensuring any snapshots are handled properly when mounting snapshotted filesystems.

looking at changelog for the lvm2 package in gutsy, it seems that it now causes these modules to be loaded in the initramfs itself. I'll assume it'll also work for lvm2 with evms, but I haven't tried it.

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Luke Andrew (luke.andrew) said : 		#4

as above, problem solved.