Code review comment for lp:~hopem/charms/trusty/percona-cluster/min-cluster-size

> Oh and yes, bootstrap-pxc is idempotent.

Excellent.

Just to be clear bootstrap-pxc *will* be run more than once. After the cluster has been bootstrapped any config-changed run that changes the config file will "re-bootstrap" on the leader. This may not be your intent.

In config-changed bootstrapped is defaulted to False and therefore the leader will run render_config_restart_on_changed with bootstrap=True:

            elif clustered and is_leader():
                log("Leader unit - bootstrap required=%s" % (not bootstrapped),
                    DEBUG)
                render_config_restart_on_changed(clustered, hosts,
                                                 bootstrap=not bootstrapped)

And in render_config_restart_on_changed if the config file has been changed it will "re-bootstrap" rather than restart:

    if file_hash(MY_CNF) != pre_hash:
        if bootstrap:
            service('bootstrap-pxc', 'mysql')
            notify_bootstrapped()
            update_shared_db_rels()
        else:
            service_restart('mysql')