[ClusterLabs] Pacemaker startup-fencing

[Ferenc Wágner]

Hi,

Pacemaker explained says about this cluster option:

    Advanced Use Only: Should the cluster shoot unseen nodes? Not using
    the default is very unsafe!

1. What are those "unseen" nodes?

And a possibly related question:

2. If I've got UNCLEAN (offline) nodes, is there a way to clean them up,
   so that they don't get fenced when I switch them on?  I mean without
   removing the node altogether, to keep its capacity settings for
   example.

And some more about fencing:

3. What's the difference in cluster behavior between
   - stonith-enabled=FALSE (9.3.2: how often will the stop operation be retried?)
   - having no configured STONITH devices (resources won't be started, right?)
   - failing to STONITH with some error (on every node)
   - timing out the STONITH operation
   - manual fencing

4. What's the modern way to do manual fencing?  (stonith_admin
   --confirm + what?  I ask because meatware.so comes from
   cluster-glue and uses the old API).
-- 
Thanks,
Feri