Table of Contents

1. Challenge

   Set the root Database User's Password and Create a Database User Account

   The database nodes are running and connected to the cluster, however the root user's password has not been set. You must first set the root user's password by running the mysql_secure_installation script:

   sudo mysql_secure_installation
   

   Now you can connect to the database as the root user and create a user account:

   mysql -u root -p
   

   Once connected, you can use the following SQL to create a user named remote who is able to login remotely. Be sure to replace mypasswd with a password of your choice.

   create user remote identified by 'mypasswd';
   grant usage on *.* to 'remote'@'%' identified by 'mypasswd';
   

2. Challenge

   Install the Prerequisite Packages

   sudo yum -y install git autoconf automake libtool gcc-c++ nmap-ncat
   

3. Challenge

   Build the Galera Load Balancer Binaries

   git clone https://github.com/codership/glb
   cd glb
   ./bootstrap.sh
   ./configure
   make
   sudo make install
   

4. Challenge

   Configure and Start Galera Load Balancer

   sudo cp /home/cloud_user/glb/files/mysql.sh /usr/local/bin/mysql-check.sh
   sudo cp /home/cloud_user/glb/files/glbd.sh /etc/init.d/glb
   

   Create glbd configuration file:

   sudo vi /etc/sysconfig/glbd
   

   # Address to listen for client connections at. Mandatory parameter.
   # To bind to all interfaces only port should be specified.
   LISTEN_ADDR="10.0.1.100:13306"
   
   # Address for controlling connection. Mandatory part is port.
   # If not specified control socket will not be opened
   CONTROL_ADDR="127.0.0.1:4444"
   
   # Target servers for client connections, space separated.
   # Target specification: IP[:PORT[:WEIGHT]] (WEIGHT and PORT optional)
   # WEIGHT defaults to 1, PORT defaults to LISTEN_ADDR port.
   DEFAULT_TARGETS="10.0.1.100:3306:10 10.0.1.110:3306:1"
   
   # Other glbd options if any as they would appear on the command line.
   OTHER_OPTIONS="--single --watchdog exec:'/usr/local/bin/mysql-check.sh -uremote -pmypasswd'"
   

   Start the service:

   sudo service glb start
   sudo service glb status
   

5. Challenge

   Confirm Connections to Primary and Replica Nodes

   Connect to the primary node via the load balancer:

   mysql -h 10.0.1.100 -P 13306 -u remote -p
   

   The connection is sent to the single server with the highest weight of those available, in this case node0.

   Connections to the replica can be made directly on port 3306:

   mysql -h 10.0.1.110 -P 3306 -u remote -p
   

6. Challenge

   Promote Replica to Primary

   A replica node can become the primary node by changing each of their weights:

   service glb add 10.0.1.100:3306:1
   service glb add 10.0.1.110:3306:10
   

   Confirm connections are routed to node1:

   mysql -h 10.0.1.100 -P 13306 -u remote -p
   service glb status