For per_node STONITH, have each node configure its own resources only

We have some races when creating STONITH resources because nodes are
creating resources at the same time. It turns out that, in the case of
crowbar, we can have each node configure its own resources only because
we know all nodes will run the code.

attributes/default.rb

@@ -46,6 +46,12 @@ default[:pacemaker][:stonith][:clone][:plugin] = ""
 default[:pacemaker][:stonith][:clone][:params] = {}
 
 default[:pacemaker][:stonith][:per_node][:plugin] = ""
+# This can be "all" or "self":
+#   - if set to "all", then every node will configure the stonith resources for
+#     all nodes in the cluster
+#   - if set to "self", then every node will configure the stonith resource for
+#     itself only
+default[:pacemaker][:stonith][:per_node][:mode] = "all"
 # This hash will contain parameters for each node. See documentation for
 # default[:pacemaker][:stonith][:clone][:params] about the format.
 # For instance:

recipes/stonith.rb

@@ -76,6 +76,10 @@ when "per_node"
   end
 
   node[:pacemaker][:stonith][:per_node][:nodes].keys.each do |node_name|
+    if node[:pacemaker][:stonith][:per_node][:mode] == "self"
+      next unless node_name == node[:hostname]
+    end
+
     stonith_resource = "stonith-#{node_name}"
     params = node[:pacemaker][:stonith][:per_node][:nodes][node_name][:params]