From 60eba01502fe34ef5d8fed9c3eee5455cb85e4e3 Mon Sep 17 00:00:00 2001
From: Kiall Mac Innes <kiall@hp.com>
Date: Fri, 9 May 2014 13:54:37 +0100
Subject: [PATCH] Improve percona cluster initialization

* Switch from /etc/init.d/mysql bootstrap-pxc to
  /etc/init.d/mysql restart-bootstrap when bootstrapping
  a new cluster. This ensures that, even when Percona starts
  at boot, that new config is loaded and the cluster is
  bootstrapped.

* If percona fails to bootstrap or restart, ensure we do not
  touch the initialized file, allowing os-refresh-config to
  try again on the next iteration.

Co-Authored-By: Gregory Haynes <greg@greghaynes.net>
Change-Id: Ia720e40329a1d39db2e25fc917fbf5b5ea85dedc
---
 .../configure.d/52-mysql-init                 | 25 +++++++++++++------
 1 file changed, 18 insertions(+), 7 deletions(-)

diff --git a/elements/mysql/os-refresh-config/configure.d/52-mysql-init b/elements/mysql/os-refresh-config/configure.d/52-mysql-init
index 5e60307ce..375650071 100755
--- a/elements/mysql/os-refresh-config/configure.d/52-mysql-init
+++ b/elements/mysql/os-refresh-config/configure.d/52-mysql-init
@@ -12,10 +12,10 @@ if [ ! -e ${MYSQL_INITIALIZED} ]; then
         # Needed to setup initial tables. This command is idempotent.
         /usr/local/mysql/scripts/mysql_install_db --user=mysql --basedir=/usr/local/mysql --datadir=/mnt/state/var/lib/mysql --no-defaults --pid-file=$pid_path  --wsrep-new-cluster
 
-        # We install this init script so we can trust this path exists
-        /etc/init.d/mysql bootstrap-pxc
-
-        touch ${MYSQL_INITIALIZED}
+        # We install this init script so we can trust this path exists.
+        # Use of restart-bootstrap vs bootstrap-pxc ensures that, even if
+        # MySQL is running, the bootstrap will succeed.
+        /etc/init.d/mysql restart-bootstrap
     elif [ $? -eq 1 ]; then
         if grep -qE '^wsrep_cluster_address[[:space:]]*=[[:space:]]*gcomm://[[:space:]]*$' /etc/mysql/conf.d/cluster.cnf; then
             echo "We are configured as joiner and have no nodes configured for the cluster. Refusing to proceed until cluster nodes are known."
@@ -23,12 +23,23 @@ if [ ! -e ${MYSQL_INITIALIZED} ]; then
         fi
 
         os-svc-restart -n mysql
-
-        touch ${MYSQL_INITIALIZED}
     else
         echo "We are neither cluster initializer or joiner. Refusing to bootstrap mysql cluster until role is known."
         exit 1
     fi
+
+    # Ensure we actually have a working database, the Percona init script does not
+    # always exit with a non zero code upon failure.
+    if [ ! -S /var/run/mysqld/mysqld.sock ]; then
+        echo "MySQL Socket missing, is percona running correctly?"
+        exit 1
+    fi
+
+    # Finally, perform a MySQL "ping". This will succeed even when MySQL returns
+    # an "Access Denied" packet, avoiding the need to provide valid credentials.
+    /usr/local/mysql/bin/mysqladmin ping
+
+    touch ${MYSQL_INITIALIZED}
 else
     # For single node setups we can re-bootstrap if were not currently running
     # We need to ensure we are bootstrap host to prevent our regex succeeding
@@ -36,7 +47,7 @@ else
     LOCAL_IP=$(os-apply-config --key local-ipv4 --type netaddress --key-default '')
     if os-is-bootstrap-host && grep -Eq "^wsrep_cluster_address=gcomm://$LOCAL_IP,?\$" /etc/mysql/conf.d/cluster.cnf; then
         if ! /etc/init.d/mysql status; then
-            /etc/init.d/mysql bootstrap-pxc
+            /etc/init.d/mysql restart-bootstrap
         fi
     fi
 fi