[dm-devel] Shared snapshots test

[Mikhail Klepachevskyy <mikhailk1 open-e com>]

Hello!

I tried to test multisnapshots but unfortunately got some errors.
Here is what I did:

1) Build vanilla linux-2.6.33 kernel using Ubuntu Desktop 9.10
   config-2.6.31-19-generic config file with
   CONFIG_DM_MULTISNAPSHOT=m
   CONFIG_DM_MULTISNAPSHOT_MIKULAS=m
   CONFIG_DM_MULTISNAPSHOT_DANIEL=m
   lines added and with patches from http://people.redhat.com/mpatocka/patches/kernel/new-snapshots/r16/
   imposed.

2) reboot with new kernel

3) # modprobe dm-store-mikulas

   # modprobe dm-multisnapshot

   # pvcreate /dev/sdb

   # vgcreate vg1 /dev/sdb

   # lvcreate --size=500M --name=lv1 vg1

   # lvcreate --size=500M --name=lv2 vg1

   # dd if=/dev/zero of=/dev/mapper/vg1-lv2 bs=4096 count=1

   # echo 0 `blockdev --getsize /dev/mapper/vg1-lv1` multisnapshot \
     /dev/mapper/vg1-lv1 /dev/mapper/vg1-lv2 16 0 mikulas 0\
	 | dmsetup create ms

   # dmsetup message /dev/mapper/ms 0 create

   # echo 0 `blockdev --getsize /dev/mapper/vg1-lv1` multisnap-snap \
     /dev/mapper/vg1-lv1 0 | dmsetup create ms0

At this point I got the next error:
device-mapper: reload ioctl failed: No such file or directory
Command failed

And these lines appeared in dmesg:
[ 6876.506623] device-mapper: table: 252:3: multisnap-snap: Snapshot with this id doesn't exist
[ 6876.506629] device-mapper: ioctl: error adding target to table

Could you check all the steps I performed right and what could cause
those error messages?

-- 
Best wishes,
Mikhail Klepachevskyy