You usually use read replicas to configure replication between Amazon RDS DB instances. For general information about read replicas, see Working with read replicas. For specific information about working with read replicas on Amazon RDS for MySQL, see Working with MySQL read replicas. Show
You can use global transaction identifiers (GTIDs) for replication with RDS for MySQL. For more information, see Using GTID-based replication for Amazon RDS for MySQL. You can also set up replication between an RDS for MySQL DB instance and a MariaDB or MySQL instance that is external to Amazon RDS. For information about configuring replication with an external source, see Configuring binary log file position replication with an external source instance. For any of these replication options, you can use either row-based replication, statement-based, or mixed replication. Row-based replication only replicates the changed rows that result from a SQL statement. Statement-based replication replicates the entire SQL statement. Mixed replication uses statement-based replication when possible, but switches to row-based replication when SQL statements that are unsafe for statement-based replication are run. In most cases, mixed replication is recommended. The binary log format of the DB instance determines whether replication is row-based, statement-based, or mixed. For information about setting the binary log format, see Configuring MySQL binary logging. Topics
OverviewClustering provides high availability and disaster recovery, along with the ability to read-scale both locally and globally. Some clusters even provide active/active capabilities, while others have a single master. Real-time MySQL database replication is a must for clustering and other key business purposes, like reporting. There are a number of replication types available for MySQL, and some are even bundled into various solutions. When choosing a replication technology, it is paramount to understand just how the data moves from source to target. In this blog post, we will examine how asynchronous, synchronous, and "semi-synchronous" MySQL replication behave when used for clustering. Also, we will explore how MySQL replication type affects database performance and data availability. Asynchronous ReplicationAsynchronous replication (async for short) is used by MySQL natively as well as by our own Tungsten Replicator. With async, all replication is decoupled from the database. Specifically, replication is a background process that reads events from the binary log on disk and makes those events available to the slaves upon request. There is no change to how the application works, and thus is quick and easy to implement. Also, async does not slow down the response from MySQL to the application. With asynchronous replication, you have:
Synchronous ReplicationUsed by Galera and its variants, synchronous replication (sync for short) addresses the above data loss issues by guaranteeing that all transactions are committed on all nodes at database commit. Synchronous replication will wait until all nodes have the transaction committed before providing a response to the application, as opposed to asynchronous replication which occurs in the background after a commit to the master. With the sync method, you can be sure that if you commit a transaction, that transaction will be committed on every node. With synchronous replication, you have:
Semi-Synchronous Replication“Semi-Synchronous Replication,” used early on by Facebook and YouTube, attempts to merge the advantages of both asynchronous and semi-synchronous replication. With semi-synchronous replication (semi-sync for short), transactions are committed on the master, transferred to at least one slave node but NOT NECESSARILY committed. At this point, control is handed back to the application and commits to the slaves are handled in the background. Compared to synchronous replication, applications can potentially be more responsive since they receive control back sooner (though it is not as fast as async). Also, compared to async, there is less chance of data loss and potentially less replication lag. With semi-synchronous replication, you have:
Why does Tungsten Clustering choose Asynchronous Replication?Tungsten Clustering uses the Tungsten Replicator, leveraging asynchronous replication, so that complex clusters can be deployed at geo scale without modifying or impacting applications or database servers. When deploying over wide area networks, asynchronous replication is the best and usually only option to protect application performance. Also, even over fast LAN’s, for write-intensive workloads, asynchronous replication is the best choice because the bottom-line impact to the application is minimized. Look out for Part 2 of this blog, that will dive into how different MySQL replication types impact cluster behavior in day-to-day operations (such as failover, local and global replication breaks, zero downtime, maintenance updates, etc.). For more information about Tungsten clusters, please visit www.continuent.com/products/tungsten-clustering If you would like to speak with one of our team, please feel free to reach out here: https://www.continuent.com/contact What are the types of replication in MySQL?There are two core types of replication format, Statement Based Replication (SBR), which replicates entire SQL statements, and Row Based Replication (RBR), which replicates only the changed rows. You can also use a third variety, Mixed Based Replication (MBR).
What is database replication in MySQL?Replication enables data from one MySQL database server (the source) to be copied to one or more MySQL database servers (the replicas). Replication is asynchronous by default; replicas do not need to be connected permanently to receive updates from the source.
Does MySQL support master master replication?MySQL Master Master replication is a development of master-slave replication that addresses its major flaws. This method of replication requires two or more master nodes that can handle both read and write requests. Additionally, each of your masters can have several slave nodes.
Which of the following is one of the correct topologies of MySQL replication?Circular Replication (also known as ring topology) is a known and common setup for MySQL replication.
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