Recently, I had a client that had a rack-mounted server that went into a hard lock on a Saturday morning. Monday morning, when it could be rebooted, MySQL received the dreaded "Last_IO_Error: Got fatal error 1236 from master when reading data from binary log: 'Could...
MySQL Blog Posts
Prevent Xtrabackup Failures for MySQL after Linux OS Patching
Patching the operating system is essential to keeping your server secure and performing optimally. Patching is as easy as running an apt-get update and apt-get upgrade. However, this can cause some unintended consequences. For one, MySQL server will also be upgraded...
Automating Log Rotation with Logrotate
Rotating MySQL logs is important because logs can take up a lot of disk space if left unmanaged. For example, an untuned database can lead to a lot of slow queries being logged. The error log can become large if it includes notes and warnings. Additionally, binlogs...
The Elements of a Bash Script
Database administrators need to know databases as well as the operating system (OS) their database is running on. Bash scripting is where the two merge. For the beginner, bash scripting can be intimidating, but all have the same basic structure: a beginning, middle,...
Simple Steps for Rotating the Error Log
The error log is an important tool for troubleshooting. The size of the error log file can get quite large if left unattended. For starters, there are not many parameters that can be adjusted to impact its size in any way, unlike the binlog that has a few system...
Start Using Binlogs: A Quick Guide
Binary logs play an important role in replication and data recovery. In replication, source databases communicate data changes recorded in its binary logs to the replica's relay logs. They can also be used to repair a replica experiencing data drift. In a similar way,...
Prepping for MySQL 5.7 Upgrade
MySQL 5.6 reached its end-of-life (EOL) in February 2021. If you haven't upgraded to MySQL 5.7, you are not the only one. It can be an intimidating endeavor. There are configuration, system table, server, Innodb and SQL changes to consider. And, documentation is not...
Migrating from SUPER to Dynamic Privileges
When performing health checks on a database, I look at how many users are granted SUPER privileges. If you're reading this, you know why. SUPER privileges pose a potential security risk and should be limited to a few users that need this far-reaching access to...
Percona XtraBackup Example
For this example, the following software versions were in use: Ubuntu v20.04.3MySQL server v5.7.35Percona XtraBackup v2.4.24 It is important to note that Percona XtraBackup 8.0 is not compatible with MySQL version 5.7 and was introduced for use with MySQL version 8.0....
MariaDB Galera Cluster WSREP_SST_METHOD Explained
This blog article will explain what the SST method choices are and what you need to consider when choosing one over another. To start with, the wsrep_sst_method is a configuration parameter used with Galera Clustering. This parameter tells the database server which...