Control node

Adding a control node

If a control node is also used as network node, storage node or compute node the corresponding instructions can be found in the corresponding chapters.

Before deploying the OpenStack services, all necessary infrastructure services should be added.

If the default inventory is used it is sufficient to add the new node to the control group.


Always add the new control node as the last host in the group. This is really important. If the new control node is added in the first place, strange things can happen.


By adding Memcached and RabbitMQ on the control node, all OpenStack services on the compute nodes and network nodes need to be reconfigured. It is recommended to combine this with an already pending maintenance of the nodes and not to do this at the same time as adding the control node.


osism-kolla deploy loadbalancer -e kolla_serial=1


osism-kolla deploy kibana -l testbed-node-2.osism.local


osism-kolla deploy elasticsearch -e kolla_serial=1


osism-kolla deploy redis -l testbed-node-2.osism.local


osism-kolla deploy memcached -l testbed-node-2.osism.local



OSISM manager version 2020.1 is necessary for the scaling of RabbitMQ. Support only from Rocky on.

osism-kolla deploy rabbitmq

After deployment, the following commands are executed on the new node. The following steps are only necessary if Rocky is used.

docker exec -it rabbitmq rabbitmqctl stop_app
Stopping rabbit application on node 'rabbit@testbed-node-2'
docker exec -it rabbitmq rabbitmqctl reset
Resetting node 'rabbit@testbed-node-2'
docker exec -it rabbitmq rabbitmqctl start_app
Starting node 'rabbit@testbed-node-2'


  • A backup should be created prior to execution.

  • It is recommended that you first clean up the individual databases before you start.

  • When adding a new node to the MariaDB Galera cluster, the new node is fully synchronized. Depending on the size of the database this may take some time.

  • When adding the new node, the existing nodes are restarted. There may be a short interruption in availability during this time.

osism-kolla deploy mariadb


osism-kolla deploy grafana -l testbed-node-2.osism.local

Open vSwitch

This step is only needed if the control node is also used as network node or compute node.

osism-kolla deploy openvswitch -l testbed-node-2.osism.local


This step is performed for each OpenStack service available in the environment.

Due to a restart of the API and scheduler/conductor services this step may cause a short interruption of availability.

Depending on the OpenStack service -e kolla_serial=1 can be used. This is not possible for every OpenStack service. Especially not for Keystone.

osism-kolla deploy SERVICE -l control

Removing a control node