diff --git a/tests/distro-regression/tests/bundles/bionic-ussuri.yaml b/tests/distro-regression/tests/bundles/bionic-ussuri.yaml
index 2446e955..a9875707 100644
--- a/tests/distro-regression/tests/bundles/bionic-ussuri.yaml
+++ b/tests/distro-regression/tests/bundles/bionic-ussuri.yaml
@@ -237,6 +237,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: ussuri/edge
   glance-simplestreams-sync:
     charm: ch:glance-simplestreams-sync
diff --git a/tests/distro-regression/tests/bundles/focal-ussuri-ovn-22.03.yaml b/tests/distro-regression/tests/bundles/focal-ussuri-ovn-22.03.yaml
index fe9030e6..7dbb8944 100644
--- a/tests/distro-regression/tests/bundles/focal-ussuri-ovn-22.03.yaml
+++ b/tests/distro-regression/tests/bundles/focal-ussuri-ovn-22.03.yaml
@@ -264,6 +264,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: ussuri/edge
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/focal-ussuri.yaml b/tests/distro-regression/tests/bundles/focal-ussuri.yaml
index eb20b7e5..84eaf118 100644
--- a/tests/distro-regression/tests/bundles/focal-ussuri.yaml
+++ b/tests/distro-regression/tests/bundles/focal-ussuri.yaml
@@ -279,6 +279,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
@@ -295,6 +296,7 @@ applications:
     options:
       amp-image-tag: 'octavia-amphora'
       retrofit-series: *series
+    constraints: mem=4096
     channel: *openstack-channel
 relations:
 - - nova-cloud-controller:amqp
diff --git a/tests/distro-regression/tests/bundles/focal-victoria.yaml b/tests/distro-regression/tests/bundles/focal-victoria.yaml
index 03200df1..ee282463 100644
--- a/tests/distro-regression/tests/bundles/focal-victoria.yaml
+++ b/tests/distro-regression/tests/bundles/focal-victoria.yaml
@@ -280,6 +280,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/focal-wallaby.yaml b/tests/distro-regression/tests/bundles/focal-wallaby.yaml
index 05364b6b..6c1a3298 100644
--- a/tests/distro-regression/tests/bundles/focal-wallaby.yaml
+++ b/tests/distro-regression/tests/bundles/focal-wallaby.yaml
@@ -306,6 +306,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/focal-xena.yaml b/tests/distro-regression/tests/bundles/focal-xena.yaml
index d304fff6..36eb0027 100644
--- a/tests/distro-regression/tests/bundles/focal-xena.yaml
+++ b/tests/distro-regression/tests/bundles/focal-xena.yaml
@@ -306,6 +306,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/focal-yoga.yaml b/tests/distro-regression/tests/bundles/focal-yoga.yaml
index 724d7f9f..71456ed3 100644
--- a/tests/distro-regression/tests/bundles/focal-yoga.yaml
+++ b/tests/distro-regression/tests/bundles/focal-yoga.yaml
@@ -306,6 +306,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/jammy-antelope.yaml b/tests/distro-regression/tests/bundles/jammy-antelope.yaml
index 967e4ee8..138a9841 100644
--- a/tests/distro-regression/tests/bundles/jammy-antelope.yaml
+++ b/tests/distro-regression/tests/bundles/jammy-antelope.yaml
@@ -323,6 +323,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/jammy-bobcat.yaml b/tests/distro-regression/tests/bundles/jammy-bobcat.yaml
index 205471dd..f7671f4c 100644
--- a/tests/distro-regression/tests/bundles/jammy-bobcat.yaml
+++ b/tests/distro-regression/tests/bundles/jammy-bobcat.yaml
@@ -2,13 +2,13 @@ variables:
   source: &source cloud:jammy-bobcat/proposed
   openstack-origin: &openstack-origin cloud:jammy-bobcat/proposed
   retrofit-uca-pocket: &retrofit-uca-pocket bobcat
-  openstack-channel: &openstack-channel latest/edge
-  ceph-channel: &ceph-channel latest/edge
-  ovn-channel: &ovn-channel latest/edge
-  mysql-channel: &mysql-channel latest/edge
-  rabbitmq-channel: &rabbitmq-channel latest/edge
+  openstack-channel: &openstack-channel 2023.2/edge
+  ceph-channel: &ceph-channel reef/edge
+  ovn-channel: &ovn-channel 23.09/edge
+  mysql-channel: &mysql-channel 8.0/edge
+  rabbitmq-channel: &rabbitmq-channel 3.9/edge
   memcached-channel: &memcached-channel latest/edge
-  vault-channel: &vault-channel latest/edge
+  vault-channel: &vault-channel 1.8/edge
 
 series: &series jammy
 applications:
@@ -320,6 +320,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/jammy-yoga.yaml b/tests/distro-regression/tests/bundles/jammy-yoga.yaml
index 20453cee..dcf0287d 100644
--- a/tests/distro-regression/tests/bundles/jammy-yoga.yaml
+++ b/tests/distro-regression/tests/bundles/jammy-yoga.yaml
@@ -305,6 +305,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
@@ -321,6 +322,7 @@ applications:
     options:
       amp-image-tag: 'octavia-amphora'
       retrofit-series: *series
+    constraints: mem=4096
     channel: *openstack-channel
 relations:
 - - nova-cloud-controller:amqp
diff --git a/tests/distro-regression/tests/bundles/jammy-zed.yaml b/tests/distro-regression/tests/bundles/jammy-zed.yaml
index 51694d3c..c9cabb33 100644
--- a/tests/distro-regression/tests/bundles/jammy-zed.yaml
+++ b/tests/distro-regression/tests/bundles/jammy-zed.yaml
@@ -304,6 +304,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/lunar-antelope.yaml b/tests/distro-regression/tests/bundles/lunar-antelope.yaml
index 563e9363..ce4dcaf1 100644
--- a/tests/distro-regression/tests/bundles/lunar-antelope.yaml
+++ b/tests/distro-regression/tests/bundles/lunar-antelope.yaml
@@ -340,6 +340,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router
diff --git a/tests/distro-regression/tests/bundles/mantic-bobcat.yaml b/tests/distro-regression/tests/bundles/mantic-bobcat.yaml
index bc6cc615..dffc8cc5 100644
--- a/tests/distro-regression/tests/bundles/mantic-bobcat.yaml
+++ b/tests/distro-regression/tests/bundles/mantic-bobcat.yaml
@@ -1,7 +1,7 @@
 variables:
   source: &source proposed
   openstack-origin: &openstack-origin distro-proposed
-  # Set retrofit-series to jammy because kinetic images aren't
+  # Set retrofit-series to jammy because mantic images aren't
   # available by default.
   retrofit-series: &retrofit-series jammy
   openstack-channel: &openstack-channel latest/edge
@@ -325,6 +325,7 @@ applications:
       openstack-origin: *openstack-origin
       spare-pool-size: 2
       loadbalancer-topology: 'ACTIVE_STANDBY'
+    constraints: mem=4096
     channel: *openstack-channel
   octavia-mysql-router:
     charm: ch:mysql-router