cvm

llthosts is required by LLT, giving each node an id.  If llthosts is missing the LLT will not start, which mean GAB will not start, which means VCS will not start, except in the case of a one node cluser where llt and gab are not required in which case you can start VCS with "hastart -onenode" without gab and llt.

The main.cf defines what node starts a service and where to failover this service (SystemList)

ServiceGroup does nodes have a restart limit attibute - it has a OnlineRetryLimit and if this is set to 1 and a critical resource fails,then first VCS tries to restart the group on this node and if he not,then this group will fail over.  You can have a RestartLimit on a resource (this is the norm, rather than at group level) and whether resource is critical or not, if resource fails then VCS will try to restart the resource - if the restart fails, AND resource is critcal then group will fail over?

You can import a non shared disk group as shared by simply using "-s" flag - similiarly you can deport a shared diskgroup and then import without "-s" to make it a non shared disk group

To shutdown a node on any cluster, CVM or failover cluster:

1. Stop any clients accessing application and complete any work in progress on the app if applicable
2. Offline all VCS application service groups (using hagrp -offline or GUI)
3. Shutdown VCS (hastop -local)
4. Shutdown server

If you just shutdown using O/S shutdown command, then this may work as shutdown script calls hastop with flags to evacuate service groups, but issues could be:

1. Application maybe shutdown forcefully if it doesn't offline quickly enough
2. Sometimes service groups get stuck and so hastop does not complete and node does not shutdown
3. Service group may have issues starting on failover node, so you shoud make sure your service is up on failover node before shuting down node (unless shutting down all nodes)

Mike