This article explains how MySQL master‑slave replication works, covering its role in high‑availability and read/write separation, the responsibilities of the master and slave servers, the IO and SQL threads, common replication topologies, and the step‑by‑step data flow from binlog to relay log.
This article analyzes a MySQL master‑slave replication failure where the SQL thread stopped with error 1594, detailing log inspection, CRC checks, relay‑log corruption, root‑cause identification, and step‑by‑step remediation procedures for restoring replication.
This guide walks through a real‑world MySQL master‑slave sync failure caused by a corrupted relay log, explains the replication mechanics, shows how to analyze slave status, use GTID to skip the bad transaction, and fully restore synchronization with step‑by‑step commands and screenshots.
This article explains a MySQL master‑slave synchronization failure caused by a corrupted relay log, walks through the replication principles, analyzes slave status and GTID differences, and provides step‑by‑step commands to skip the problematic GTID and restore replication.
This article analyzes how MySQL slave crashes can cause inconsistencies between master info and relay log positions during sync_master_info and sync_relay_log_info processes, presents case studies of duplicated events, explains the impact of different storage repositories (FILE vs TABLE), and recommends configuration settings to achieve server‑crash‑safe replication.
This article examines how slave crashes in MySQL replication can cause inconsistencies between master info and relay log positions, leading to duplicate events and errors such as 1062 and 1032, analyzes underlying mechanisms, presents case studies, and proposes configuration settings to achieve server‑crash‑safe replication.
This article explains the structure and purpose of the MySQL slave_relay_log_info table, how relay log positions are persisted and synchronized, the role of master_auto_position and GTID, and the mechanisms of relay_log_recovery to ensure reliable replication after crashes.
The article examines MySQL 5.6’s crash‑safe slave replication, explaining how earlier versions’ unsafe relay‑log handling could corrupt position data, describing the atomic update of mysql.slave_relay_log_info via table‑based relay‑log info and transaction coordination, and covering configuration options, recovery behavior, GTID implications, performance trade‑offs, and implementation guidance.
After switching a MySQL master’s IP, the author observed unusually high traffic between master and slave, investigated the role of GTID, semi‑sync and the CHANGE MASTER command, and demonstrated that executing CHANGE MASTER on a lagging replica can clear the relay‑log and cause a temporary traffic surge as the missing binlog entries are re‑fetched.
After switching a MySQL master’s IP, the author observed extreme master‑to‑slave traffic and investigated whether using CHANGE MASTER with auto_position=1 forces the replica to re‑fetch already executed binlogs, especially when the replica is lagging.
The article explains how MySQL replication parameters such as expire_logs_days, relay-log-recovery, and relay-log-info-repository affect binlog cleanup, SQL and I/O thread consistency, and why crashes can produce duplicate‑key errors, then offers configuration fixes including the critical relay‑log cleaning option and the super_read_only setting.
