Comment 3 for bug 1779310

Relations with this service are:

~$ juju config cinder-ssd enabled-services
volume
~$ juju status cinder-ssd --relations | egrep cinder-ssd:
cinder-ssd:cinder-volume-service nova-cloud-controller:cinder-volume-service cinder regular
cinder-ssd:cluster cinder-ssd:cluster cinder-ha peer
cinder-ssd:juju-info filebeat:beats-host juju-info subordinate
cinder-ssd:nrpe-external-master nrpe:nrpe-external-master nrpe-external-master subordinate
glance:image-service cinder-ssd:image-service glance regular
mysql:shared-db cinder-ssd:shared-db mysql-shared regular
rabbitmq-server:amqp cinder-ssd:amqp rabbitmq regular
ssd-storage:storage-backend cinder-ssd:storage-backend cinder-backend subordinate

COMMON_PACKAGES includes apache2 and haproxy. Those packages should be only installed, configured and managed if cinder-api service is enabled.

Same about nrpe.add_haproxy_checks (in update_nrpe_config function). Method needs to be called when cinder-api service is enabled in the unit.