Sahara will always be installed by default with OSP 9. Operators should be able to choose wether to enable Sahara and possibly leave it disabled by default.

Implementing a parameter like ControllerEnableSahara would be ideal and simple enough to add a conditional to /usr/share/openstack-tripleo-heat-templates/puppet/manifests/overcloud_controller_pacemaker.pp in the Sahara section.

As a workaround, to disable it I had to do the following:

1. Disable it in haproxy using controllerExtraConfig:

parameter_defaults:
 controllerExtraConfig:
  tripleo::loadbalancer::sahara: false

2. Remove the pcs resources via script in NodeExtraConfigPost. Note I couldn't find any way via puppet and extraconfig to do this. Something like this in a script run from NodeExtraConfigPost will do:

            #!/bin/sh
            if [[ `hostname` = *"controller"* ]]
            then
              pcs resource delete openstack-sahara-api
              pcs resource delete openstack-sahara-engine
            fi

3. Remove the endpoint manually: I can't find any way to disable this other than modifying /usr/lib/python2.7/site-packages/tripleoclient/constants.py and removing 'sahara' from SERVICE_LIST. It doesn't look like there's a clean way to patch /usr/lib/python2.7/site-packages/tripleoclient/v1/overcloud_deploy.py to achieve this. With the current implementation it seems it's all or nothing.