From e63c86aab0bad71b67077516880a0d8949b2561c Mon Sep 17 00:00:00 2001
From: Nicholas Randon <nicholas.randon@hp.com>
Date: Thu, 15 Jan 2015 15:38:14 +0000
Subject: [PATCH] Prevent unclustered RabbitMQ with 0 nodes

It can happen that RabbitMQ attempts to start before Heat has delivered
rabbit.nodes. It comes through as a blank value, IE with 0 nodes in it,
causing the Rabbit post-configure script to think we want a
non-clustered Rabbit config. This is not limited to one node - all nodes
will attempt to start non-clustered.

They can then start receiving messages, which makes joining a cluster
later difficult. To avoid this situation, first of all only allow the
bootstrap node to come up non-clustered. If you want a non-clustered
config you must have a single node control plane already so this is
fine.

Do not configure at all if we don't know who the bootstrap node is. Nor
should even the bootstrap node configure as non-clustered if we can see
other nodes are clustered.

Change-Id: Ib2ec261c84143640a5ccd1abbc99be1c8020c543
---
 .../post-configure.d/51-rabbitmq              | 21 +++++++++----------
 1 file changed, 10 insertions(+), 11 deletions(-)

diff --git a/elements/rabbitmq-server/os-refresh-config/post-configure.d/51-rabbitmq b/elements/rabbitmq-server/os-refresh-config/post-configure.d/51-rabbitmq
index 37b815b3f..dfdf040ac 100755
--- a/elements/rabbitmq-server/os-refresh-config/post-configure.d/51-rabbitmq
+++ b/elements/rabbitmq-server/os-refresh-config/post-configure.d/51-rabbitmq
@@ -2,34 +2,34 @@
 set -eux
 set -o pipefail
 
+BOOTSTRAP_NODE="$(os-apply-config --key bootstrap_host.bootstrap_nodeid --type netaddress --key-default '')"
 LOCAL_RABBIT_HOST="$(os-apply-config --key bootstrap_host.nodeid --type netaddress --key-default '')"
 NODES=$(os-apply-config --key rabbit.nodes --type raw --key-default '' | sed 's/,/\n/g' | sort)
 # convert nodes to lowercase because rabbitmq uses hostname locally, hostname
 # is lowercased by cloud-init. If uppercase is used for node names then
 # there would be mismatch.
+BOOTSTRAP_NODE=${BOOTSTRAP_NODE,,}
 LOCAL_RABBIT_HOST=${LOCAL_RABBIT_HOST,,}
 NODES=(${NODES,,})
 TOTAL_NODES=${#NODES[@]}
 
-
-
 # Insufficient meta-data to attempt to start-up RabbitMQ.
-if [ -z "${LOCAL_RABBIT_HOST}" ]; then
-    echo "RabbitMQ bootstrap_host.nodeid is not defined in meta-data, aborting."
+if [ -z "${LOCAL_RABBIT_HOST}" -o -z "${BOOTSTRAP_NODE}" ]; then
+    echo "RabbitMQ bootstrap_host details are not fully defined in heat meta-data, aborting."
     exit 255
 fi
 
 os-svc-enable -n rabbitmq-server
 
 ## Non-cluster configuration set-up. ##
-if [ ${TOTAL_NODES} -le 1 ]; then
+if [ ${TOTAL_NODES} -le 1 -a \
+       "${BOOTSTRAP_NODE}" == "${LOCAL_RABBIT_HOST}" ] &&
+           ! rabbitmq_is_in_cluster; then
     os-svc-restart -n rabbitmq-server
     echo "RabbitMQ non-cluster configuration complete..."
     exit 0
 fi
 
-BOOTSTRAP_NODE="$(os-apply-config --key bootstrap_host.bootstrap_nodeid --type netaddress --key-default '')"
-BOOTSTRAP_NODE=${BOOTSTRAP_NODE,,}
 NODE_INDEX=""
 # Find the nodes being worked on in the NODES array.
 for (( index = 0; index < ${TOTAL_NODES}; index++ )); do
@@ -38,11 +38,10 @@ for (( index = 0; index < ${TOTAL_NODES}; index++ )); do
     fi
 done
 
-if [ -z "${BOOTSTRAP_NODE}" -o ${TOTAL_NODES} -lt 3 -o -z "${NODE_INDEX}" ]; then
-    #      We do not know who the bootstrap is, why are we attempting to bring up a Rabbit cluster?
-    # -OR- we do not have sufficient nodes to support HA so lets abort.
+if [ ${TOTAL_NODES} -lt 3 -o -z "${NODE_INDEX}" ]; then
+    #      We do not have sufficient nodes to support HA so lets abort.
     # -OR- we did not find our node in the array and hence did not set node_indexs.
-    echo "bootstrap_host.bootstrap_nodeid: ${BOOTSTRAP_NODE}, TOTAL_NODES: ${TOTAL_NODES}, NODE_INDEX: ${NODE_INDEX}"
+    echo "TOTAL_NODES: ${TOTAL_NODES}, NODE_INDEX: ${NODE_INDEX}"
     echo "RabbitMQ cluster configuration prerequisites not met, aborting."
     exit 255
 fi