diff --git a/lib/tempest b/lib/tempest
index 0bac72e985..c2cad80446 100644
--- a/lib/tempest
+++ b/lib/tempest
@@ -559,9 +559,8 @@ function configure_tempest {
         tox -revenv-tempest --notest
     fi
 
-    # The requirements might be on a different branch, while tempest needs master requirements.
-    (cd $REQUIREMENTS_DIR && git show origin/master:upper-constraints.txt) > u-c-m.txt
-    tox -evenv-tempest -- pip install -c u-c-m.txt -r requirements.txt
+    # NOTE(gmann): Use branch constraint because Tempest is pinned to the branch release instead of using master.
+    tox -evenv-tempest -- pip install -c $REQUIREMENTS_DIR/upper-constraints.txt -r requirements.txt
 
     # Auth:
     iniset $TEMPEST_CONFIG auth tempest_roles "Member"
@@ -671,9 +670,10 @@ function install_tempest {
 function install_tempest_plugins {
     pushd $TEMPEST_DIR
     if [[ $TEMPEST_PLUGINS != 0 ]] ; then
-        # The requirements might be on a different branch, while tempest & tempest plugins needs master requirements.
+        # NOTE(gmann): Use branch constraint because Tempest is pinned to the branch release
+        # instead of using master.
         (cd $REQUIREMENTS_DIR && git show origin/master:upper-constraints.txt) > u-c-m.txt
-        tox -evenv-tempest -- pip install -c u-c-m.txt $TEMPEST_PLUGINS
+        tox -evenv-tempest -- pip install -c $REQUIREMENTS_DIR/upper-constraints.txt $TEMPEST_PLUGINS
         echo "Checking installed Tempest plugins:"
         tox -evenv-tempest -- tempest list-plugins
     fi
diff --git a/stackrc b/stackrc
index ff85146c90..3b0891c25b 100644
--- a/stackrc
+++ b/stackrc
@@ -309,8 +309,11 @@ REQUIREMENTS_REPO=${REQUIREMENTS_REPO:-${GIT_BASE}/openstack/requirements.git}
 REQUIREMENTS_BRANCH=${REQUIREMENTS_BRANCH:-$TARGET_BRANCH}
 
 # Tempest test suite
-TEMPEST_REPO=${TEMPEST_REPO:-${GIT_BASE}/openstack/tempest.git}
-TEMPEST_BRANCH=${TEMPEST_BRANCH:-$BRANCHLESS_TARGET_BRANCH}
+TEMPEST_REPO=${TEMPEST_REPO:-https://review.opendev.org/openstack/tempest}
+# Use Tempest commit (for tag 21.0.0) which is Queens supported version.
+# https://docs.openstack.org/releasenotes/tempest/v21.0.0.html
+# https://github.com/openstack/tempest/commit/abd07b42ca01319c2e289dc60e0449069e2889df
+TEMPEST_BRANCH=${TEMPEST_BRANCH:-refs/changes/99/670699/1}
 
 
 ##############
diff --git a/tests/test_refs.sh b/tests/test_refs.sh
index 0f9aa4a5ca..1bd3a8b5af 100755
--- a/tests/test_refs.sh
+++ b/tests/test_refs.sh
@@ -15,7 +15,7 @@
 
 echo "Ensuring we don't have crazy refs"
 
-REFS=`grep BRANCH stackrc | grep -v 'TARGET_BRANCH' | grep -v 'NOVNC_BRANCH'`
+REFS=`grep BRANCH stackrc | grep -v 'TARGET_BRANCH' | grep -v 'NOVNC_BRANCH' | grep -v TEMPEST_BRANCH`
 rc=$?
 if [[ $rc -eq 0 ]]; then
     echo "Branch defaults must be one of the *TARGET_BRANCH values. Found:"