Update: relay-log.info no longer exists, you need to use SHOW MASTER STATUS;, see https://dev.mysql.com/doc/refman/5.7/en/replication-howto-masterstatus.html

How to set up a new Mysql replicator, based heavily on this blogpost

– Rsync database from existing secondary server (source):
rsync -Sa --progress --exclude=mastername* --exclude=master.info --exclude=relay-log.info /var/lib/mysql/* new_server:/var/lib/mysql
– pause replication on original secondary server
mariadb> stop slave
– cat relay-log.info

./mysqld-relay-bin.000875
208022
mysql-bin.000294
445713389
2

4

– re-rsync
– resume replication on original secondary server
mariadb>start slave
– disable replication on new server by adding ‘skip-slave-start’ to my.cnf
– start mariadb on new server
– set relay bin and mysql bin data on new server

# mysqlbinlog --start-position=208022 ./mysqld-relay-bin.000875 | mysql -p
mariadb> CHANGE MASTER TO MASTER_HOST='', MASTER_USER='', MASTER_PASSWORD='', MASTER_LOG_FILE='mysql-bin.000294', MASTER_LOG_POS=445713389
– start replication
mariadb> start slave
– check replication status
mariadb> show slave status\G
– remove skip-slave-start from my.cnf
– enjoy!