(Ryan to review)
Omission of ricci and modclusterd from the cluster-related services
being automatically enabled at boot on the nodes upon creating/adding
an existing cluster.
The vital step of enabling ricci and, less strictly, modclusterd services
on cluster nodes for a smooth cluster run across its life-cycle is up
the cluster's administrator, because neither is enabled at boot by default
upon its installation. In addition, when a user opted in to the reboot
the cluster nodes while creating it, luci will not be able to finish this
task properly until the user's intervention or if not performed in advance.
(note: mentioned within point 4:
When creating a cluster or adding the existing one, luci will include
enabling ricci and modclusterd into the execution sequence to be
performed by each of the node during the process.
After the cluster is created/added in the fixed luci, no user's intervention
regarding enabling ricci and modclusterd services at boot is needed for
a smooth cluster life-cycle.