[stable-only] gate: Pin CEPH_RELEASE to nautilus in LM hook

I1edd5a50079f325fa143a7e0d51b3aa3bb5ed45d moved the branchless
devstack-plugin-ceph project to the Octopus release of Ceph that drops
support for py2. As this was still the default on stable/train this
breaks the nova-live-migration and nova-grenade jobs.

This change works around this by pinning the CEPH_RELEASE to nautilus
within the LM hook as was previously used prior to the above landing.

Note that the devstack-plugin-ceph-tempest job from the plugin repo
continues to pass as it is correctly pinned to the Luminous release that
supports py2.

If anything the above enforces the need to move away from these hook
scripts and instead inherit our base ceph jobs from this repo in the
future to avoid the Ceph release jumping around like this.

NOTE(lyarwood): Conflicts due to the partial backport of
I902e459093af9b82f9033d58cffcb2a628f5ec39 in stable/queens.

Conflicts:
    nova/tests/live_migration/hooks/run_tests.sh

Change-Id: I1d029ebe78b16ed2d4345201b515baf3701533d5
(cherry picked from commit ff570d1b4e9b9777405ae75cc09eae2ce255bf19)
(cherry picked from commit 436e8172f65193e177a4a12780f752dbc7e88b39)
(cherry picked from commit 238c83a2f778a9c2f0abbe318dda97b715926565)

2 files changed, 6 insertions, 0 deletions

diff --git a/nova/tests/live_migration/hooks/ceph.sh b/nova/tests/live_migration/hooks/ceph.sh
index ff94967748..2a2ec0202c 100755
--- a/nova/tests/live_migration/hooks/ceph.sh
+++ b/nova/tests/live_migration/hooks/ceph.sh
@@ -8,6 +8,7 @@ function prepare_ceph {
     configure_ceph
     #install ceph-common package on compute nodes
     $ANSIBLE subnodes --become -f 5 -i "$WORKSPACE/inventory" -m raw -a "executable=/bin/bash
+    export CEPH_RELEASE=nautilus
     source $BASE/new/devstack/functions
     source $BASE/new/devstack/functions-common
     git clone https://git.openstack.org/openstack/devstack-plugin-ceph /tmp/devstack-plugin-ceph
diff --git a/nova/tests/live_migration/hooks/run_tests.sh b/nova/tests/live_migration/hooks/run_tests.sh
index 9e85159bd3..8edd797525 100755
--- a/nova/tests/live_migration/hooks/run_tests.sh
+++ b/nova/tests/live_migration/hooks/run_tests.sh
@@ -53,6 +53,11 @@ if [ "$GRENADE_OLD_BRANCH" ]; then
     echo '2. test with Ceph is skipped due to bug 1813216'
 else
     echo '3. test with Ceph for root + ephemeral disks'
+    # NOTE(lyarwood): Pin the CEPH_RELEASE to nautilus here as was the case
+    # prior to https://review.opendev.org/c/openstack/devstack-plugin-ceph/+/777232
+    # landing in the branchless plugin, we also have to pin in ceph.sh when
+    # configuring ceph on a remote node via ansible.
+    export CEPH_RELEASE=nautilus
     GetOSVersion
     prepare_ceph
     GLANCE_API_CONF=${GLANCE_API_CONF:-/etc/glance/glance-api.conf}