MySQL replication is reasonably stable, and no less so than other solutions. But there are a variety of failures that can happen, without it being MySQL’s fault. Binlogs can develop corrupted packets in transit due to network glitches. MySQL 5.6 introduced binlog checksums to detect this.
Is MySQL replication safe?
The “safeness” of a statement in MySQL Replication, refers to whether the statement and its effects can be replicated correctly using statement-based format. If this is true of the statement, we refer to the statement as safe; otherwise, we refer to it as unsafe.
Does MySQL replication affect performance?
To give a simple answer to your question, “No, replication does not kill the performance of your master.” Replication enables data from one MySQL server (the master) to be replicated to one or more MySQL servers (the slaves).
How does MySQL replication work?
The MySQL replication feature allows a server – the master – to send all changes to another server – the slave – and the slave tries to apply all changes to keep up-to-date with the master. … The master has a thread, called the dump thread, that continuously reads the master’s binlog and sends it to the slave.
Why does MySQL replicate?
Replication enables data from one MySQL database server (known as a source) to be copied to one or more MySQL database servers (known as replicas). … Scale-out solutions – spreading the load among multiple replicas to improve performance. In this environment, all writes and updates must take place on the source server.
What is MySQL group replication?
MySQL Group Replication is a MySQL Server plugin that enables you to create elastic, highly-available, fault-tolerant replication topologies. … There is a built-in group membership service that keeps the view of the group consistent and available for all servers at any given point in time.
What is MySQL cluster vs replication?
In a replication setup, a master MySQL server updates one or more slaves. … In MySQL Cluster, all data nodes are kept in synchrony, and a transaction committed by any one data node is committed for all data nodes. In the event of a data node failure, all remaining data nodes remain in a consistent state.
How do I monitor MySQL replication?
Replication is best monitored by checking the following variables:
- SLAVE_RUNNING: This is a global status variable and its value can be checked using SHOW GLOBAL STATUS like ‘slave_running’. …
- If slave_running is ‘ON’, then the slave is up and working fine, which means both the SQL thread and the IO thread are running.
How do you deal with lag replication?
To mitigate replication lag for large operations we use batching. We never apply a change to 100,000 rows all at once. Any big update is broken into small segments, subtasks, of some 50 or 100 rows each. As an example, say our app needs to purge some rows that satisfy a condition from a very large table.
What are the two basic styles of data replication?
Replication environments support two basic types of sites: master sites and snapshot sites. A master site maintains a complete copy of all objects in a replication group.
Is MySQL replication push or pull?
That is, it pulls the data from the source, rather than the source pushing the data to the replica. The replica also executes the events from the binary log that it receives. … For more information on the specifics of the replication implementation, see Section 16.2. 3, “Replication Threads”.
How does data replication work?
How data replication works. Replication involves writing or copying the same data to different locations. For example, data can be copied between two on-premises hosts, between hosts in different locations, to multiple storage devices on the same host, or to or from a cloud-based host.
How do I know if MySQL replication is working?
Check MySQL Replication Status on Query Servers
- Start the MySQL command-line utility on the slave server: # cd /opt/mysql/mysql/bin. …
- Check the replication status using the show slave status command (the status of the slave server is conveyed by the Slave_IO_Running and Slave_SQL_Running column values):
How do I enable MySQL replication?
Get MySQL Replication up and running in 5 minutes
- Step 1: Edit the configuration files & start the MySQL Servers. The first step in setting up replication involves editing the “my. …
- Step 2: Create Replication User. …
- Step 3: Initialize Replication. …
- Step 4: Basic Checks. …
- 21 responses.
What is E in MySQL?
-e is actually short for –execute , that’s probably why you had trouble finding it. http://dev.mysql.com/doc/refman/5.7/en/mysql-command-options.html#option_mysql_execute. Execute the statement and quit. The default output format is like that produced with –batch.