EBS snapshots and LVM2

I've been meaning to try this for a while to see how it goes - use LVM2 to take an "instantaneous" snapshot of an EBS volume and then let AWS take it's time. I found LVM wasn't as quick as I'd like. Also, I have performance tested this either, so I don't know how bad the latency will be. Either way, I think it's an easy way to get a consistent backup:

# prep
export MYAZ="us-east-1a"
# create 1st EBS volume and attach
ec2-create-volume --size 2 --availability-zone $MYAZ
export VOL0="vol-XXXXXXXX"
ec2-attach-volume $VOL0 --instance $MYINST --device /dev/sdf

# create LVM partition 1
fdisk /dev/sdf
# add to LVM
pvcreate /dev/sdf1
# create a volume group
vgcreate vol0 /dev/sdf1
# create a logical volume
lvcreate -l80%FREE -n test vol0
# format it
mke2fs -j -m0 /dev/vol0/test
# mount it
mkdir -p /mnt/vol0/test
mount /dev/vol0/test /mnt/vol0/test

# lock data consistently

# create LVM snapshot
lvcreate -L300M -s -n test2 /dev/vol0/test

# unlock data consistently

# create EBS snapshot
ec2-create-snapshot $VOL0
export VOL0_SNAP="snap-XXXXXXXX"

# remove LVM snapshot
lvremove vol0/test2

# create 2nd EBS volume from snapshot and attach
ec2-create-volume --snapshot $VOL0_SNAP --availability-zone $MYAZ
export VOL1="vol-YYYYYYYY"
ec2-attach-volume $VOL1 --instance $MYINST --device /dev/sdf

# import snapshot as new volume group
vgimportclone -n vol1 /dev/sdg1
# activate new volume group
vgchange -a y vol1
# mount it
mkdir -p /mnt/vol1/test2
mount /dev/vol1/test2 /mnt/vol1/test2

EDIT 2013.02.10: "lock data consistently" - I highly recommend "fsfreeze" which is built into most Linux distributions nowadays.

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