Public bug reported: Description =========== When we use nfs backend in cinder and attach a cinder volume to an instance, the instance access to the file in nfs share, which is named like volume-<volume id>.
When the volume is attached to an instance and we take snapshot with "openstack volume snapshot create <volume> --force", it will create the following 3 files in nfs share. (1) volume-<volume id> base image freezed when taking snapshot (2) volume-<volume id>-<snapshot id> diff image where instance should write into after taking snapshot (3) volume-<volume id>.info json file to manage active snapshot As described above, after taking snapshot, the instance should write into (2) volume-<volume id>-<snapshot id> . It works just after taking snapshot, but if we stop and start the instance, the instance starts to write into (1) volume-<volume id>, which it should not modify. Steps to reproduce ================== 1. Create a volume in cinder nfs backend 2. Create a bfv instance with the volume 3. Take snapshot of the volume 4. Stop and Start the instance Expected result =============== The instance keeps writing into volume-<volume id>-<snapshot id> Actual result ============= The instance writes into volume-<volume id> Environment =========== I reproduced the issue with Queens release with nova: libvirt driver cinder: nfs backed, with nfs_snapshot_support=True As far as I see the implementation about file path handling, I don't see any changes in the way how we handle disk file path for nfs backend, so the problem should be reproduced with master. Logs & Configs ============== N/A ** Affects: nova Importance: Undecided Status: New -- You received this bug notification because you are a member of Yahoo! Engineering Team, which is subscribed to OpenStack Compute (nova). https://bugs.launchpad.net/bugs/1860913 Title: Instance uses base image file when it is rebooted after snapshot creation if cinder nfs backend is used Status in OpenStack Compute (nova): New Bug description: Description =========== When we use nfs backend in cinder and attach a cinder volume to an instance, the instance access to the file in nfs share, which is named like volume-<volume id>. When the volume is attached to an instance and we take snapshot with "openstack volume snapshot create <volume> --force", it will create the following 3 files in nfs share. (1) volume-<volume id> base image freezed when taking snapshot (2) volume-<volume id>-<snapshot id> diff image where instance should write into after taking snapshot (3) volume-<volume id>.info json file to manage active snapshot As described above, after taking snapshot, the instance should write into (2) volume-<volume id>-<snapshot id> . It works just after taking snapshot, but if we stop and start the instance, the instance starts to write into (1) volume-<volume id>, which it should not modify. Steps to reproduce ================== 1. Create a volume in cinder nfs backend 2. Create a bfv instance with the volume 3. Take snapshot of the volume 4. Stop and Start the instance Expected result =============== The instance keeps writing into volume-<volume id>-<snapshot id> Actual result ============= The instance writes into volume-<volume id> Environment =========== I reproduced the issue with Queens release with nova: libvirt driver cinder: nfs backed, with nfs_snapshot_support=True As far as I see the implementation about file path handling, I don't see any changes in the way how we handle disk file path for nfs backend, so the problem should be reproduced with master. Logs & Configs ============== N/A To manage notifications about this bug go to: https://bugs.launchpad.net/nova/+bug/1860913/+subscriptions -- Mailing list: https://launchpad.net/~yahoo-eng-team Post to : yahoo-eng-team@lists.launchpad.net Unsubscribe : https://launchpad.net/~yahoo-eng-team More help : https://help.launchpad.net/ListHelp