Replication

Giriş

Master-Slave Replication için şunlar kullanılabilir

1. Asynchronous

2. Synchronous

3. Semi-synchronous

Master-Slave veya Master-Master Replication için şunlar kullanılabilir

1. Group Replication

 Asynchronous Replication

 Asynchronous Replication yazısına taşıdım

Synchronous Replication

Açıklaması şöyle. Master tüm replica'ların da transaction'ı commit etmesini bekler.

With fully synchronous replication, when a source commits a transaction, all replicas have also committed the transaction before the source returns to the session that performed the transaction. Fully synchronous replication means failover from the source to any replica is possible at any time. The drawback of fully synchronous replication is that there might be a lot of delay to complete a transaction.

Semi-synchronous Replication

Semi-synchronous Replication yazısına taşıdım

Group Replication

Açıklaması şöyle

Groups can operate in a single-primary mode with automatic primary election, where only one server accepts updates at a time. Alternatively, groups can be deployed in multi-primary mode, where all servers can accept updates, even if they are issued concurrently.

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. Servers can leave and join the group and the view is updated accordingly. Sometimes servers can leave the group unexpectedly, in which case the failure detection mechanism detects this and notifies the group that the view has changed. This is all automatic.

Group Replication guarantees that the database service is continuously available. However, it is important to understand that if one of the group members becomes unavailable, the clients connected to that group member must be redirected, or failed over, to a different server in the group, using a connector, load balancer, router, or some form of middleware. Group Replication does not have an inbuilt method to do this. For example, see MySQL Router 8.0.