Adding a New Compute Node to Existing Containerized Contrail Cluster

Assume Contrail cluster is successfully provisioned by the following instances.yaml file.

provider_config:                                                                                
  bms:
    ssh_pwd: c0ntrail123
    ssh_user: root
    ntpserver: x.x.x.x
    domainsuffix: local
instances:
  srvr1:
    provider: bms
    ip: 192.168.1.51
    roles:
      config_database:
      config:
      control:
      analytics_database:
      analytics:
      webui:
      openstack:
  srvr2:
    provider: bms
    ip: 192.168.1.52
    roles:
      config_database:
      config:
      control:
      analytics_database:
      analytics:
      webui:
      openstack:
  srvr3:
    provider: bms
    ip: 192.168.1.53
    roles:
      config_database:
      config:
      control:
      analytics_database:
      analytics:
      webui:
      openstack:
  srvr4:                                                       
    provider: bms
    ip: 192.168.1.54
    roles:
      vrouter:
      openstack_compute:
contrail_configuration:
  CONTRAIL_VERSION: 5.1.0-0.40-ocata
  CONTROL_DATA_NET_LIST: 192.168.10.0/24
  RABBITMQ_NODE_PORT: 5673
  VROUTER_GATEWAY: 192.168.10.1
  IPFABRIC_SERVICE_HOST: 192.168.10.150
  KEYSTONE_AUTH_URL_VERSION: /v3
kolla_config:
  kolla_globals:
    kolla_internal_vip_address: 192.168.10.150
    kolla_external_vip_address: 192.168.1.150

1. Edit the instances.yaml file to add a compute node, srvr5.
   content_copy zoom_out_map

   provider_config:                                                                                 
     bms:
       ssh_pwd: c0ntrail123
       ssh_user: root
       ntpserver: x.x.x.x
       domainsuffix: local
   instances:
     srvr1:
       provider: bms
       ip: 192.168.1.51
       roles:
         config_database:
         config:
         control:
         analytics_database:
         analytics:
         webui:
         openstack:
     srvr2:
       provider: bms
       ip: 192.168.1.52
       roles:
         config_database:
         config:
         control:
         analytics_database:
         analytics:
         webui:
         openstack:
     srvr3:
       provider: bms
       ip: 192.168.1.53
       roles:
         config_database:
         config:
         control:
         analytics_database:
         analytics:
         webui:
         openstack:
     srvr4:                                                       
       provider: bms
       ip: 192.168.1.54
       roles:
         vrouter:
         openstack_compute:
     srvr5:                                                       
       provider: bms
       ip: 192.168.1.55
       roles:
         vrouter:
         openstack_compute:
   
   contrail_configuration:
     CONTRAIL_VERSION: 5.1.0-0.38-ocata
     CONTROL_DATA_NET_LIST: 192.168.10.0/24
     RABBITMQ_NODE_PORT: 5673
     VROUTER_GATEWAY: 192.168.10.1
     IPFABRIC_SERVICE_HOST: 192.168.10.150
     KEYSTONE_AUTH_URL_VERSION: /v3
   kolla_config:
     kolla_globals:
       kolla_internal_vip_address: 192.168.10.150
       kolla_external_vip_address: 192.168.1.150

2. Run the configure_instances.yml playbook with the new instances.yaml file.
   ansible-playbook -i inventory/ -e orchestrator=openstack playbooks/configure_instances.yml

   It will install the required software and also, prepare the new node for running the relevant containers.

3. Run playbooks.
   ansible-playbook -i inventory/ -e orchestrator=openstack --tags nova playbooks/install_openstack.yml
ansible-playbook -i inventory/ -e orchestrator=openstack playbooks/install_contrail.yml
   Note

   The --tags nova option runs only the nova role so that the other containers are not affected.

   It is not recommended to omit the above option. If the option is omitted, especially when multiple OpenStack nodes are running with HA, the MariaDB Galera cluster will go out of sync and will not converge. In such situation, the only solution is to re-provision the entire OpenStack cluster.

You can also add or remove a compute node to existing Contrail cluster using Contrail Command UI. For details, refer to Adding a New Compute Node to Existing Containerized Contrail Cluster Using Contrail Command.