Let’s take a deeper look into MySQL master-master replication disadvantages

Bobcares answers all questions no matter the size, as part of our MySQL support, to help you through understanding the MySQL master-master replication disadvantages

Let us take a look at the disadvantages of Mysql master-master replication in detail.

MySQL Master-Master Replication

Master-slave replication is evolving into master-master replication, which addresses the majority of its problems. Assume that the user has two or more master nodes that can accept both read and write requests for this form of replication. The user can furthermore have numerous slave nodes for every master. Asynchronous replication occurs between master nodes.

Disadvantages

1. The MySQL master-master replication user may lose certain transactions if one or more master nodes fail as a result of the asynchronous replication amongst all master nodes.
2. The user cannot be certain that backups created on each master node have the same data due to asynchronous replication.
3. In the event that you need to upgrade a slave node to a master node, failover is still not entirely under automation.

Consider that A and B are set up by the user as master-master. Both A and B must be read-only replicas, with A serving as the main master. The user can switch to B as the primary master to take down A. The mysql master-master replication is already set up for the other way by the user. Nothing has to undergo configuration. The modifications made to B will undergo replay whenever the user brings A back online.

The user may choose to perform the MySQL master-master replication manually at the moment of failover. However, it’s an extra step that the consumer needn’t take. It only makes the failover process more difficult.

The drawbacks or disadvantages are as follows:

1. If B is set with log slave update, binary logs from B can send back to A, increasing the amount of bandwidth used by the network.
2. If the user unintentionally makes a modification on B directly, A will receive a copy of it. This could result in a split brain.
3. The user will spend an unexpected amount of time explaining master-master replication to other team members and reassuring them that it’s OK.

[Need assistance with similar queries? We are here to help]

Conclusion

To conclude, When compared to MySQL master-slave replication, MySQL master-master replication has certain disadvantages and it addresses them.