Disable ironic exporter by default

To ensure backwards compatibility, disable the ironic exporter by
default. Enabling it requires the prometheus-ironic-exporter group to
be present in the ansible inventory, and may have a performance impact.

This commit makes the feature "opt-in"

kolla/defaults.yml

@@ -284,7 +284,7 @@ prometheus_server_external_url: "{{ public_protocol }}://{{ prometheus_external_
 prometheus_alertmanager_external_url: "{{ public_protocol }}://{{ prometheus_external_fqdn }}:{{ prometheus_alertmanager_port }}"
 prometheus_bind_address: "{{ lookup('vars', 'ansible_' + network_interface).ipv4.address }}"
 
-enable_prometheus_ironic_exporter: "{{ enable_prometheus | bool and enable_ironic | bool }}"
+enable_prometheus_ironic_exporter: no
 
 # Redfish Monitor
 redfish_monitor_openstack_user: "{{ keystone_admin_username }}"

kolla/node_custom_config/ironic.conf

@@ -23,8 +23,12 @@ port_range = 40000:50000
 [conductor]
 # We do not perform automated cleaning to improve turnaround time on a node.
 automated_clean = False
+
+{% if enable_prometheus_ironic_exporter | bool %}
+send_sensor_data = True
 send_sensor_data_interval = "{{ ironic_send_sensor_data_interval }}"
 send_sensor_data_for_undeployed_nodes = "{{ ironic_send_sensor_data_for_undeployed_nodes }}"
+{% endif %}
 
 # deploy kernel and ramdisk to use if not set on node
 {% if ironic_deploy_kernel is defined %}