8.7. Modifying the Overcloud Environment

Sometimes you might intend to modify the Overcloud to add additional features, or change the way it operates. To modify the Overcloud, make modifications to your custom environment files and Heat templates, then rerun the openstack overcloud deploy command from your initial Overcloud creation. For example, if you created an Overcloud using Chapter 7, Creating the Overcloud, you would rerun the following command:
$ openstack overcloud deploy --templates -e /usr/share/openstack-tripleo-heat-templates/environments/network-isolation.yaml -e ~/templates/network-environment.yaml -e ~/templates/storage-environment.yaml --control-scale 3 --compute-scale 3 --ceph-storage-scale 3 --control-flavor control --compute-flavor compute --ceph-storage-flavor ceph-storage --ntp-server pool.ntp.org
The director checks the overcloud stack in heat, and then updates each item in the stack with the environment files and heat templates. It does not recreate the Overcloud, but rather changes the existing Overcloud.
If you aim to include a new environment file, add it to the openstack overcloud deploy command with a -e option. For example:
$ openstack overcloud deploy --templates -e /usr/share/openstack-tripleo-heat-templates/environments/network-isolation.yaml -e ~/templates/network-environment.yaml -e ~/templates/storage-environment.yaml -e ~/templates/new-environment.yaml --control-scale 3 --compute-scale 3 --ceph-storage-scale 3 --control-flavor control --compute-flavor compute --ceph-storage-flavor ceph-storage --ntp-server pool.ntp.org
This includes the new parameters and resources from the environment file into the stack.

Important

It is advisable not to make manual modifications to the Overcloud's configuration as the director might overwrite these modifications later.