Talk about the solution to MySQL master-slave error

MySQL master-slave replication is a very important function in the MySQL database. It can synchronize data between different servers to achieve data backup and load balancing. However, master-slave replication errors due to various reasons are also common. These errors may lead to data loss, data errors and other problems. This article will introduce some solutions to MySQL master-slave replication errors to help you avoid or solve these problems.

1. Master-slave replication stops synchronization

When MySQL master-slave replication stops working, the most obvious manifestation is that the data in the master database cannot be copied to the slave database. This problem may have many causes, including network problems, master-slave database configuration errors, master-slave database version inconsistencies, etc. First, you need to check whether the configuration of the MySQL master-slave database is correct and whether the correct master-slave replication parameters are enabled, such as master_log_file, master_log_pos, etc. Secondly, you can try to restart the slave database and restart the master database.

If the problem persists, you can view the status of the replication thread. Enter the SHOW SLAVE STATUS command on the command line and check the values ​​of the two parameters Slave_IO_Running and Slave_SQL_Running in the output. If both values ​​are Yes, the master-slave replication should run normally. If one or both values ​​are No, then Further troubleshooting is required.

2. Partial data is lost from the database

Partial data is lost from the database is a very common master-slave replication problem, which is usually caused by errors in the replication thread of. The solution to this problem includes the following steps:

• First, you need to check whether the network connection between the slave server and the master server is normal and whether there is a network failure or interruption;
• Secondly , you can check whether the replication thread of the slave server is running. Enter the SHOW SLAVE STATUS command on the command line and check whether the Slave_IO_Running parameter in the output is Yes. If not, you need to restart the replication thread on the slave server;
• If the above steps cannot solve the problem, you need to shut down MySQL from the server and reset replication. Specific operations include:
• Stop the replication thread on the slave server;
• Use the STOP MASTER command on the master server to pause the write operation of the master server;
• On the slave server Delete all databases and close MySQL;
• Use the SHOW MASTER STATUS command on the master server to view the status of the master server and record its output;
• Restart MySQL on the slave server, and Use the CHANGE MASTER TO command to configure the information of the master server;
• Finally, use the START SLAVE command on the slave server to restart the replication thread.

3. Master-slave replication delay

Another problem with MySQL master-slave replication is latency, that is, the data on the slave server is not synchronized with the data on the master server. This may be caused by the replication thread not connecting fast enough, or by other issues on the slave server. If the delay is long, data corruption or loss may result.

Methods to solve this problem include:

• Optimize the network connection: You can consider using a faster network connection or upgrading the bandwidth;
• Increase the resources of the slave server: Increasing the CPU, memory and other hardware resources of the slave server can improve the processing speed of the replication thread;
• Optimize the write operation of the master server: Use the correct master-slave replication parameters to avoid lock tables or locks on the master server. Lock rows and other situations to reduce the delay of master-slave replication.

Summary

MySQL master-slave replication is a very important function in the database, but you will also encounter various problems and errors during use. However, by analyzing and solving these problems, we can better understand and master the working principle of MySQL master-slave replication, thereby better ensuring the data security of the database and enhancing the management capabilities of the database.

The above is the detailed content of Talk about the solution to MySQL master-slave error. For more information, please follow other related articles on the PHP Chinese website!