Need list of active services to be tunable

[Greg Coit]

Mercury currently doesn't support disabling local mysql and moving it to an external service (see http://groups.drupal.org/node/70503#comment-228248).

We should identify any service that could be used on a separate server (apachesolr, mysql, varnish) and allow a person to disable the local service without bcfg2 then starting it again

[Greg Coit (gregcoit)]

adding apparmor (lucid), selinux (centos) and iptables (both) to the list of services that we should add to server_tuneables

[Aaron Levy (aaronlevy)]

I have tested adding memcached/mysql/tomcat/varnish as tunable services.

On CentOS it works well. The services are turned off/on properly with changes to the server_tunable file.

On Ubuntu, it works but with some caveats:
 - 'deb' services will not be restarted on bcfg2 client runs, a restart or manual service start are necessary.
 - 'upstart' services currently have a bug where they will not be restarted by bcfg2 either. See https://bugs.launchpad.net/pantheon/+bug/594798

This means that if you tune a service to be off, it will turn off properly. However, if you set the tunable back to default/ON then it will not be started until reboot or you manually restart the service. This is obviously less than ideal.

Until there is a definite need for this functionality I'm going to hold off committing. Attached is the bzr diff of what is needed for including this type of functionality when we do want to enable it in the future. Essentially, a probe checks the tunable value & if set, it assigns the client to a group like "service-name-off" and we have rules for that group that turn the service on or off.

[Damien McKenna (damienmckenna)]

I had added ticket #596161, which has been labeled as a duplicate of this.