Nova Cell

  • By OpenStack Charmers
Channel Version Revision Published Runs on
latest/stable 1 1 11 Mar 2022
Ubuntu 12.04
latest/edge 1 1 11 Mar 2022
Ubuntu 12.04
juju deploy nova-cell
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Cells functionality allows an OpenStack Compute cloud to be scalled in a more distributed fashion without using complicated technologies like database and message queue clustering. It is intended to support very large deployments.

This charm allows distinct cells to be setup with each cell having its own nova-cloud-controller, database and rabbit servers. The cells are then related together into parent and child relation with the top most cell being the api cell which has no compute resource.


  • Neutron is not cell aware and it requires its own database and message broker.
  • Due to bug #1348103 nova-compute should be deployed with vif_plugging_timeout set > 0
  • Message broker SSL is currently not supported

Deployment topologies

Child cells can optionally have children themselves:

     |         |          |
  child1     child2     child3
         |           |
      child20     child21

Where a cell sits in the topology is decided by its juju relation with other cells. For the example above the following cell relations exist:

api:nova-cell-parent child1:nova-cell-child api:nova-cell-parent child2:nova-cell-child api:nova-cell-parent child3:nova-cell-child child2:nova-cell-parent child20:nova-cell-child child2:nova-cell-parent child21:nova-cell-child