MariaDB Galera Cluster on AlmaLinux 9

Overview

MariaDB Galera Cluster provides synchronous multi-master replication.

Nodes:

• Node 1: 192.168.1.10
• Node 2: 192.168.1.11
• Node 3: 192.168.1.12

Step 1 – Install MariaDB with Galera on all nodes

dnf install -y mariadb-server-galera galera

Step 2 – Configure Node 1 (/etc/mysql/conf.d/galera.cnf)

[mysqld]
binlog_format            = ROW
default-storage-engine   = innodb
innodb_autoinc_lock_mode = 2
bind-address             = 0.0.0.0

# Galera Provider
wsrep_on                 = ON
wsrep_provider           = /usr/lib/galera/libgalera_smm.so

# Cluster
wsrep_cluster_name       = "mariadb_cluster"
wsrep_cluster_address    = "gcomm://192.168.1.10,192.168.1.11,192.168.1.12"

# Node
wsrep_node_address       = "192.168.1.10"
wsrep_node_name          = "node1"

wsrep_sst_method         = rsync

Step 3 – Bootstrap Node 1

systemctl stop mariadb
galera_new_cluster

Verify:

SHOW STATUS LIKE 'wsrep_cluster_size';   -- should be 1

Step 4 – Start remaining nodes

Configure identically (change wsrep_node_address and wsrep_node_name), then on each node:

systemctl start mariadb

Step 5 – Verify all nodes joined

SHOW STATUS LIKE 'wsrep_cluster_size';   -- should be 3
SHOW STATUS LIKE 'wsrep_incoming_addresses';