Use disableHostNodeID param in values.yaml to configure Consul client (…

…hashicorp#901)

* Use disableHostNodeID param in values.yaml to configure Consul client
* Remove comment about multi-agent testing since this will be a DaemonSet
* Add bats tests for disableHostNodeID

templates/client-daemonset.yaml

@@ -191,7 +191,7 @@ spec:
                 -node-meta=pod-name:${HOSTNAME} \
                 -node-meta=host-ip:${HOST_IP} \
                 -hcl='leave_on_terminate = true' \
-                -disable-host-node-id=false \
+                -disable-host-node-id={{ .Values.client.disableHostNodeID }} \
                 {{- if .Values.global.tls.enabled }}
                 -hcl='ca_file = "/consul/tls/ca/tls.crt"' \
                 {{- if .Values.global.tls.enableAutoEncrypt }}

test/unit/client-daemonset.bats

@@ -1206,3 +1206,27 @@ rollingUpdate:
   local actual=$(echo $security_context | jq -r .privileged)
   [ "${actual}" = "true" ]
 }
+
+#--------------------------------------------------------------------
+# client.disableHostNodeID
+
+@test "client/DaemonSet: disableHostNodeID defaults to false" {
+  cd `chart_dir`
+  local actual=$(helm template \
+      -s templates/client-daemonset.yaml \
+      . | tee /dev/stderr | \
+      yq '.spec.template.spec.containers[0].command | any(contains("disable-host-node-id=false"))' \
+      | tee /dev/stderr)
+  [ "${actual}" = "true" ]
+}
+
+@test "client/DaemonSet: disableHostNodeID can be set to true" {
+  cd `chart_dir`
+  local actual=$(helm template \
+      -s templates/client-daemonset.yaml \
+      --set 'client.disableHostNodeID=true' \
+      . | tee /dev/stderr | \
+      yq '.spec.template.spec.containers[0].command | any(contains("disable-host-node-id=true"))' \
+      | tee /dev/stderr)
+  [ "${actual}" = "true" ]
+}

values.yaml

@@ -699,6 +699,13 @@ client:
   # This also changes the clients' advertised IP to the `hostIP` rather than `podIP`.
   exposeGossipPorts: false
 
+  # Disable host node ID 
+  # If true, consul clients will not use information from the host to generate a deterministic node ID
+  # and will instead generate a random node ID which will be persisted in the data directory. 
+  # When two VMs are on the same underlying hardware, they can have node IDs that collide. Setting `disableHostNodeID` to true can work around the collision.
+  # Refer to https://www.consul.io/docs/agent/options#_disable_host_node_id for more info. 
+  disableHostNodeID: false
+
   # Resource settings for Client agents.
   # NOTE: The use of a YAML string is deprecated. Instead, set directly as a
   # YAML map.