Group Replication – Consistency Levels

The MySQL Group Replication (GR) feature is a multi-primary update anywhere or single-primary replication plugin for MySQL with built-in conflict detection and resolution, automatic distributed recovery, and group membership.

Its goal it is to make high-availability (HA) simple with off-the-shelf hardware, not only to new applications but also existing ones – that was one of the motivations of the single-primary mode.…

How to manually decrypt an encrypted binary log file

The encrypted binary log file format introduced in MySQL version 8.0.14 was designed to allow a “manual” decryption of the file data when the value of the key that encrypted its file password is known.

Each encrypted binary (or relay) log file is composed by an encrypted binary log file header and the encrypted binary log content (the file data).…

Extending replication instrumentation: an insight on transaction retries

MySQL 8.0.13 improves replication lag monitoring by extending the instrumentation for transaction transient errors. These temporary errors, which include lock timeouts caused by client transactions executing concurrently as the slave is replicating, do not stop the applier thread: instead, they cause a transaction to retry.…

Group Replication: coping with unreliable failure detection

Failure detection is a cornerstone of distributed systems as it determines which components are working properly or not, allowing it to tackle both network and host instabilities and failures. Like many other distributed systems, Group Replication (GR) requires a majority of correctly operating group members to work properly.…