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1. Set heat::api::enabled: false and heat::engine::enabled: false and heat::api_cfn::enabled: false in hiera to stop all services
2. Run puppet with stein modules/tags
3. Run apt dist-upgrade
4. Run heat-manage db_sync on one of the api-nodes.

5. Remove the hiera keys that disabled the services and re-run puppet

Horizon

1. Add the following lines to the node-specific hiera:
   • apache::mod::wsgi::package_name: 'libapache2-mod-wsgi-py3'
   • apache::mod::wsgi::mod_path: '/usr/lib/apache2/modules/mod_wsgi.so'
2. Run puppet with the stein modules/tags
3. run apt dist-upgrade
4. Run puppet again
5. restart apache2

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