Step 3: Start and Configure MariaDB Enterprise Server on Replica Servers

Parallel Replication

Writes to the primary server that are group committed or logged with a Global Transaction ID in different replication domains can be applied on the replica server using parallel threads to improve performance.

Example Configuration

On each Enterprise Server node, edit a configuration file and set these system variables and options:

[mariadb]
bind_address = 0.0.0.0
log_bin      = mariadb-bin.log
server_id    = 1

Set the server_id option to a value that is unique for each Enterprise Server node.

Back up the Primary Server

Use MariaDB Enterprise Backup to back up the primary server.

1. On the primary server, take a full backup:

   $ sudo mariadb-backup --backup \
         --user=mariabackup_user \
         --password=mariabackup_passwd \
         --target-dir=/data/backup/replica_backup
   

   Confirm successful completion of the backup operation.

2. On the primary server, prepare the backup:

   $ sudo mariadb-backup --prepare \
         --target-dir=/data/backup/replica_backup
   

   Confirm successful completion of the prepare operation.

Restore the Backup to the Replica Server

1. On the primary server, copy the backup directory to each replica server:

   $ sudo rsync -av /data/backup/replica_backup 192.0.2.11:/data/backup/
   

2. On the replica server, move the default datadir to another location:

   $ sudo mv /var/lib/mysql /var/lib/mysql_backup
   

3. On the replica server, use MariaDB Enterprise Backup to restore the backup to the datadir:

   $ sudo mariadb-backup --copy-back \
      --target-dir=/data/backup/replica_backup
   

4. On the replica server, set the file permissions for the datadir:

   $ sudo chown -R mysql:mysql /var/lib/mysql
   

Set the Global Transaction ID Position

If the replica server was restored from a backup of the primary, set the GTID position.

1. Get the GTID position that corresponds to the restored backup. This can be found in the xtrabackup_binlong_info file.

   $ cat xtrabackup_binlog_info
   mariadb-bin.000096 568 0-1-2001,1-2-5139
   

   The GTID position from the above output is 0-1-2001,1-2-5139.

2. Connect to the replica server:

   $ sudo mariadb
   

3. Set the gtid_slave_pos system variable to the GTID position:

   SET GLOBAL gtid_slave_pos='0-1-2001,1-2-5139';
   

Start Replication

1. Execute the CHANGE MASTER TO statement to configure the replica server to connect to the primary server at this position:

   CHANGE MASTER TO
      MASTER_USER = "repl",
      MASTER_HOST = "192.0.2.10",
      MASTER_PASSWORD = "repl_passwd",
      MASTER_USE_GTID = slave_pos;
   

   The above statement configures the replica server to connect to a primary server located at 192.0.2.10 using the repl user account. This account must first be configured on the primary server.

2. Use the START REPLICA statement to start replication:

   START REPLICA;
   

3. Use SHOW REPLICA STATUS statement to confirm replication is running:

   SHOW REPLICA STATUS\G
   

   *************************** 1. row ***************************
                   Slave_IO_State: Waiting for master to send event
                      Master_Host: 192.0.2.10
                      Master_User: repl
                      Master_Port: 3306
                    Connect_Retry: 60
                  Master_Log_File: mariadb-bin.000001
              Read_Master_Log_Pos: 645
                   Relay_Log_File: li282-189-relay-bin.000002
                    Relay_Log_Pos: 946
            Relay_Master_Log_File: mariadb-bin.000001
                 Slave_IO_Running: Yes
                Slave_SQL_Running: Yes
                  Replicate_Do_DB:
              Replicate_Ignore_DB:
               Replicate_Do_Table:
           Replicate_Ignore_Table:
          Replicate_Wild_Do_Table:
      Replicate_Wild_Ignore_Table:
                       Last_Errno: 0
                       Last_Error:
                     Skip_Counter: 0
              Exec_Master_Log_Pos: 645
                  Relay_Log_Space: 1259
                  Until_Condition: None
                   Until_Log_File:
                    Until_Log_Pos: 0
               Master_SSL_Allowed: No
               Master_SSL_CA_File:
               Master_SSL_CA_Path:
                  Master_SSL_Cert:
                Master_SSL_Cipher:
                   Master_SSL_Key:
            Seconds_Behind_Master: 0
    Master_SSL_Verify_Server_Cert: No
                    Last_IO_Errno: 0
                    Last_IO_Error:
                   Last_SQL_Errno: 0
                   Last_SQL_Error:
      Replicate_Ignore_Server_Ids:
                 Master_Server_Id: 1
                   Master_SSL_Crl:
               Master_SSL_Crlpath:
                       Using_Gtid: Slave_Pos
                      Gtid_IO_Pos: 0-1-2
          Replicate_Do_Domain_Ids:
      Replicate_Ignore_Domain_Ids:
                    Parallel_Mode: optimistic
                        SQL_Delay: 0
              SQL_Remaining_Delay: NULL
          Slave_SQL_Running_State: Slave has read all relay log; waiting for more updates
                 Slave_DDL_Groups: 2
   Slave_Non_Transactional_Groups: 0
       Slave_Transactional_Groups: 0