2:09 p.m.
On Wed, Aug 15, 2018 at 6:14 PM Алексей Максимов <
aleksey.i.maksimov(a)yandex.ru> wrote:
Hello Nir
Thanks for the answer.
The output of the commands is below.
*********************************************************************************************************************************************
> 1. Please share the output of this command on one of the hosts:
> lvs -o vg_name,lv_name,tags | grep cdf1751b-64d3-42bc-b9ef-b0174c7ea068
*********************************************************************************************************************************************
# lvs -o vg_name,lv_name,tags | grep cdf1751b-64d3-42bc-b9ef-b0174c7ea068
VG LV
LV Tags
...
6db73566-0f7f-4438-a9ef-6815075f45ea
208ece15-1c71-46f2-a019-6a9fce4309b2
IU_cdf1751b-64d3-42bc-b9ef-b0174c7ea068,MD_23,PU_00000000-0000-0000-0000-000000000000
6db73566-0f7f-4438-a9ef-6815075f45ea
4974a4cc-b388-456f-b98e-19d2158f0d58
IU_cdf1751b-64d3-42bc-b9ef-b0174c7ea068,MD_15,PU_00000000-0000-0000-0000-000000000000
6db73566-0f7f-4438-a9ef-6815075f45ea
8c66f617-7add-410c-b546-5214b0200832
IU_cdf1751b-64d3-42bc-b9ef-b0174c7ea068,MD_16,PU_208ece15-1c71-46f2-a019-6a9fce4309b2
So we have 2 volumes - 2 are base volumes:
- 208ece15-1c71-46f2-a019-6a9fce4309b2
IU_cdf1751b-64d3-42bc-b9ef-b0174c7ea068,MD_23,PU_00000000-0000-0000-0000-000000000000
- 4974a4cc-b388-456f-b98e-19d2158f0d58
IU_cdf1751b-64d3-42bc-b9ef-b0174c7ea068,MD_15,PU_00000000-0000-0000-0000-000000000000
And one is top volume:
- 8c66f617-7add-410c-b546-5214b0200832
IU_cdf1751b-64d3-42bc-b9ef-b0174c7ea068,MD_16,PU_208ece15-1c71-46f2-a019-6a9fce4309b2
So according to vdsm, this is the chain:
208ece15-1c71-46f2-a019-6a9fce4309b2 <-
8c66f617-7add-410c-b546-5214b0200832 (top)
The volume 4974a4cc-b388-456f-b98e-19d2158f0d58 is not part of this chain.
*********************************************************************************************************************************************
> qemu-img info --backing /dev/vg_name/lv_name
*********************************************************************************************************************************************
# qemu-img info --backing
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/208ece15-1c71-46f2-a019-6a9fce4309b2
image:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/208ece15-1c71-46f2-a019-6a9fce4309b2
file format: qcow2
virtual size: 30G (32212254720 bytes)
disk size: 0
cluster_size: 65536
Format specific information:
compat: 1.1
lazy refcounts: false
refcount bits: 16
corrupt: false
This is the base volume according to vdsm and qemu, good.
# qemu-img info --backing
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/4974a4cc-b388-456f-b98e-19d2158f0d58
image:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/4974a4cc-b388-456f-b98e-19d2158f0d58
file format: qcow2
virtual size: 30G (32212254720 bytes)
disk size: 0
cluster_size: 65536
backing file: 208ece15-1c71-46f2-a019-6a9fce4309b2 (actual path:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/208ece15-1c71-46f2-a019-6a9fce4309b2)
backing file format: qcow2
Format specific information:
compat: 1.1
lazy refcounts: false
refcount bits: 16
corrupt: false
image:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/208ece15-1c71-46f2-a019-6a9fce4309b2
file format: qcow2
virtual size: 30G (32212254720 bytes)
disk size: 0
cluster_size: 65536
Format specific information:
compat: 1.1
lazy refcounts: false
refcount bits: 16
corrupt: false
This is the deleted volume according to vdsm metadata. We can see that this
volume
still has a backing file pointing to the base volume.
# qemu-img info --backing
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/8c66f617-7add-410c-b546-5214b0200832
image:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/8c66f617-7add-410c-b546-5214b0200832
file format: qcow2
virtual size: 30G (32212254720 bytes)
disk size: 0
cluster_size: 65536
backing file: 208ece15-1c71-46f2-a019-6a9fce4309b2 (actual path:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/208ece15-1c71-46f2-a019-6a9fce4309b2)
backing file format: qcow2
Format specific information:
compat: 1.1
lazy refcounts: false
refcount bits: 16
corrupt: false
image:
/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/208ece15-1c71-46f2-a019-6a9fce4309b2
file format: qcow2
virtual size: 30G (32212254720 bytes)
disk size: 0
cluster_size: 65536
Format specific information:
compat: 1.1
lazy refcounts: false
refcount bits: 16
corrupt: false
This is top top volume.
So I think this is what happened:
You had this chain in the past:
208ece15-1c71-46f2-a019-6a9fce4309b2 <-
4974a4cc-b388-456f-b98e-19d2158f0d5 <- 8c66f617-7add-410c-b546-5214b0200832
(top)
You deleted a snapshot in engine, which created the new chain:
208ece15-1c71-46f2-a019-6a9fce4309b2 <-
8c66f617-7add-410c-b546-5214b0200832 (top)
<-
4974a4cc-b388-456f-b98e-19d2158f0d5 (deleted)
Deleting 4974a4cc-b388-456f-b98e-19d2158f0d5 failed, but we cleared the
metadata
of this volume.
To confirm this theory, please share the output of:
Top volume:
dd if=/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/metadata bs=512 count=1
skip=16 iflag=direct
Base volume:
dd if=/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/metadata bs=512 count=1
skip=23 iflag=direct
Deleted volume?:
dd if=/dev/6db73566-0f7f-4438-a9ef-6815075f45ea/metadata bs=512 count=1
skip=15 iflag=direct
Nir