Comment 4 for bug 1694959

Going to need more details about this. What is the recreate scenario?
What type of instance is it - is it volume-backed or using nova local
disk (ephemeral)?

We are launching an instance using cinder volume-backed, when we create an snapshot of the instance as well as volume which in dashboard shows 0 byte on successfull snapshot creation.

Nova local disk(ephemeral) - when we create an snapshot it gives succeessful result and we are able to restore the volume and can launch an instance using the volume.

Are there errors in the nova-compute logs during the snapshot? Are there
errors in the Glance logs? Is a snapshot image created in glance and if
so, what are the details about that (image show output)? Is the image
uploading?

We are not seeing any error logs in compute logs as well as glance logs except below INFO from glance registery.log

2017-06-01 19:45:54.348 22298 INFO glance.registry.api.v1.images [req-e4352c36-46a5-4423-9c6d-e44eece78b11 f869753422a740299fcf6b90f58e3e63 b4839fee2f0b4141861ec7d09c03d631 - - -] Successfully created image 340edac3-6a7b-4702-97c7-071368d7ae8f
2017-06-01 19:45:54.350 22298 INFO eventlet.wsgi.server [req-e4352c36-46a5-4423-9c6d-e44eece78b11 f869753422a740299fcf6b90f58e3e63 b4839fee2f0b4141861ec7d09c03d631 - - -] 127.0.0.1 - - [01/Jun/2017 19:45:54] "POST /images HTTP/1.1" 200 1149 0.103890
2017-06-01 19:45:54.833 22300 INFO eventlet.wsgi.server [req-4db5b582-6509-4114-a041-092bf3f91513 f869753422a740299fcf6b90f58e3e63 b4839fee2f0b4141861ec7d09c03d631 - - -] 127.0.0.1 - - [01/Jun/2017 19:45:54] "GET /images/detail?sort_key=name&sort_dir=asc&limit=21 HTTP/1.1" 200 9629 0.092997
2017-06-01 19:46:05.183 22298 INFO eventlet.wsgi.server [req-e3cccc86-a4b3-4925-9538-26aaf4e8363c f869753422a740299fcf6b90f58e3e63 b4839fee2f0b4141861ec7d09c03d631 - - -] 127.0.0.1 - - [01/Jun/2017 19:46:05] "GET /images/340edac3-6a7b-4702-97c7-071368d7ae8f HTTP/1.1" 200 1149 0.065102
2017-06-01 19:46:05.290 22298 INFO eventlet.wsgi.server [req-e2aa8276-5761-4d38-91ff-9a2deb5774a9 f869753422a740299fcf6b90f58e3e63 b4839fee2f0b4141861ec7d09c03d631 - - -] 127.0.0.1 - - [01/Jun/2017 19:46:05] "GET /images/340edac3-6a7b-4702-97c7-071368d7ae8f HTTP/1.1" 200 1149 0.051132

We are not able to create an image from the snapshot since its size is "0 byte"

Which virt driver are you using? Which glance image backend are you
using?

Virt dirver is KVM

Glance image backend is Glusterfs

Please let us know if you require additional information on this.