title: Master-Master Replication [Percona]
body: <p>Please forgive my ignorance but I do not have a ton of experience with MySQL. I am a web developer but overall I have pretty much just installed MySQL or spun up an RDS instance, connected to it and everything just works. However I am currently being tasked with creating a complete backup of our primary server (essentially high availability with a load balancer etc). So I thought now might be a good time to change how I haver our MySQL setup to take advantage of having 2 servers. Currently our MySQL lives on our primary servers and that will probably stay that way for now, however my goal with this new setup is to have 2 identical servers, both running the application and both having the exact same MySQL data structure / data. I want to be able to essentially open up the web application on one server, make a change, see it on the other or vica versa.</p>
  
  <p>From my research it looks like what I want is called "Master-Master Replication" however it seems as if this is an older / more outdated approach? Every article I read is from ~2010-2012 and most people say it is depreciated and I should use Percona XtraDB Cluster, MySQL Group Replication, or Galera Cluster etc. I basically have no idea what any of that means and I am looking for the easiest way to get Master-Master type setup working. On top of that even if I wanted to use regular Master-Master replication it seems as if this is something specific to MySQL and not Percona which is what I actually use.</p>
  
  <p>I know plenty about dev ops and can get everything but the MySQL up and running in no time but I would love some insight on the best way to do this. Currently servers are running Centos 7, Percona 5.7, Apache 2.4.</p>