When you connect to a server (or cluster) using a TCP proxy level 7, also referred to as an application-level or Layer 7 proxy (highest level of the OSI model), the application doesn’t connect directly to the back-end server(s). The proxy usually understands the protocol used and can eventually take some decisions or even change the request.

The problem when using such proxy (like HA Proxy, ProxySQL and MySQL Router) is that the server doesn’t really know from where the client is connecting. The server sees the IP address of the proxy/router as the source IP of the client.

HA Proxy initially designed the Proxy Protocol, a simple protocol that allows a TCP connection to transport proxy-related information between the client, the proxy server and the destination server. The main purpose of the Proxy Protocol is then to preserve the client’s original IP address (with some others metadata). See …

With this post we are reaching the end of our journey to HA for WordPress & MySQL 8.0 on OCI.

If you have not read the two previous articles, this is just the right time.

• MySQL 8.0 InnoDB ReplicaSet with WordPress in OCI
• MySQL 8.0 InnoDB ReplicaSet with WordPress in OCI – part II

We started this trip using the MySQL InnoDB ReplicaSet where only 2 servers are sufficient but doesn’t provide automatic fail-over.

In this article we will upgrade our InnoDB ReplicaSet to …

This article is the second part of our journey to WordPress and MySQL 8.0 High Availability on OCI. The first part can be read here.

We ended part I with one webserver hosting WordPress. This WordPress was connecting locally to MySQL Router using HyperDB add-on. This add-on allows to split the reads & writes on MySQL Servers using replication. And finally we had one MySQL InnoDB ReplicaSet of two …