Increase size of connection tracking table

etc/kayobe/compute.yml

@@ -106,7 +106,8 @@
 # Compute node sysctl configuration.
 
 # Dict of sysctl parameters to set.
-#compute_sysctl_parameters:
+compute_sysctl_parameters:
+  net.netfilter.nf_conntrack_max: 1048576
 
 ###############################################################################
 # Compute node tuned configuration.

etc/kayobe/controllers.yml

@@ -115,7 +115,8 @@
 # Controller node sysctl configuration.
 
 # Dict of sysctl parameters to set.
-#controller_sysctl_parameters:
+controller_sysctl_parameters:
+  net.netfilter.nf_conntrack_max: 1048576
 
 ###############################################################################
 # Controller node tuned configuration.

etc/kayobe/storage.yml

@@ -111,7 +111,8 @@
 # Storage node sysctl configuration.
 
 # Dict of sysctl parameters to set.
-#storage_sysctl_parameters:
+storage_sysctl_parameters:
+  net.netfilter.nf_conntrack_max: 1048576
 
 ###############################################################################
 # Storage node tuned configuration.

releasenotes/notes/bump-conntrack-table-size-c2d08f2aac04d23f.yaml

@@ -0,0 +1,7 @@
+---
+fixes:
+  - |
+    Increases maximum size of connection tracking tables to 1,048,576 entries
+    on controllers, compute and storage hosts. This is to work around loss of
+    connectivity when the conntrack table becomes full under high Cinder/Glance
+    activity or high traffic to Octavia amphorae.