Recently I often faced problems with MariaDB Galera Cluster, so I decided to give Percona XtraDB Cluster a try. I write here necessary steps to setup a PHP Stack with Percona XtraDB Cluster on CentOS 7.
- To avoid problems, be sure that SELinux is not enabled in the server. Guide can be found HERE.
- Open INCOMING and OUTGOING ports for MySQL Cluster: 3306, 4444, 4567, 4568
- First, install Epel, Remi, and Percona repo for CentOS 7:
yum install -y epel-release rpm -Uvh http://rpms.famillecollet.com/enterprise/remi-release-7.rpm yum install -y https://www.percona.com/redir/downloads/percona-release/redhat/percona-release-0.1-4.noarch.rpm yum install -y yum-utils
- Switch to PHP7 repo:
yum-config-manager --enable remi-php71
- Next, install Nginx and PHP softwares:
yum install -y nginx yum install -y php-fpm php-opcache php-mysqlnd php-mcrypt php-mbstring php-cli php-opcache php-xml
- Then, install Percona XtraDB Cluster:
yum install -y Percona-XtraDB-Cluster-57
- Edit /etc/my.cnf to add information about cluster under [mysqld] section. Sample configuration is as follows:
binlog_format = ROW innodb_buffer_pool_size = 100M innodb_flush_log_at_trx_commit = 0 innodb_flush_method = O_DIRECT innodb_log_files_in_group = 2 innodb_log_file_size = 20M innodb_file_per_table = 1 datadir = /var/lib/mysql wsrep_cluster_address = gcomm://IP_NODE_1,IP_NODE_2,IP_NODE_3 wsrep_provider = /usr/lib64/galera3/libgalera_smm.so wsrep_slave_threads = 8 wsrep_cluster_name = ClusterName wsrep_node_name = NODE_NAME wsrep_node_address = IP_NODE_1 innodb_locks_unsafe_for_binlog = 1 innodb_autoinc_lock_mode = 2 wsrep_sst_method = xtrabackup-v2 wsrep_sst_auth = "AUTHUSER:AUTHPASSWORD"
- Bootstrap it in the first node
systemctl start [email protected]
service mysql bootstrap-pxc
. Remember that for other nodes, we only need to start the service without bootstrap.service param.
- Remember to Secure MySQL after installing:
- Grant permission for the above AUTHUSER for replication (or grant all permission as me):
# mysql -u root -p GRANT USAGE ON *.* to [email protected]'%' IDENTIFIED BY 'AUTHPASSWORD'; GRANT ALL PRIVILEGES on *.* to [email protected]'%'; FLUSH PRIVILEGES;
- Done, re-peat the config for NODE_2 and NODE_3. Remember to update wsrep_node_name and wsrep_node_address for these node also. As all user / password / mysql configuration will be copied from existing nodes to the new nodes, so we do not need to do many repeated tasks over and over.
WARNING: If you are enabling SELinux and cannot join a cluster, consider to DISABLE it. I found myself be difficult in activating a new joiner node when I enable SELinux, but all goes well after disabling it.