When using WordPress in an HA fault-tolerant stack on AWS, you can usually use the same processes and procedures you would use on a single-server WP installation.  But, there are some processes that, if adopted, will make using a fault-tolerant WP configuration a little less frustrating.

Plugins and Themes

The first process change we recommend you make is in uploading plugins and themes.  For plugins and themes with a lot of small files in their zips, we strongly recommend that you upload these via sFTP.  You’re less likely to get timeouts.  The EFS (elastic file system) volume has a much higher latency so unzipping a lot of small files can take quite a bit of time.  This can cause the web server to time out.  Thus, sFTP is the recommended method for uploading plugins and themes.

Of course, if you’re integrating a GIT or other version control process into your workflow then this probably doesn’t matter as much.