A plugin incompatibility is any plugin that does not properly function on our infrastructure out of the box, creates site errors and/or misbehavior, or otherwise cannot be used in our environment or within a particular type of customer environment without some tweaking.
Autoptimize
This will only affect HA server pairs
This is a widely used plugin and very popular with our customers. In a typical, single server environment, this plugin works fine, for the most part. However, in HA environments it creates an issue on the secondary node in the cluster due to the way we proxy wp-admin requests to the primary node. The autoptimize plugin writes cache to wp-content/cache/autoptimize which is unique to each installation. When it is installed in an HA environment, the cache directory is skipped and this may cause layout issues since the autoptimize files aren't present in the secondary server.
Solutions:
- Disable and stop using the autoptimize plugin.
- Change HA server setup to Active/Passive mode. This would mean that there's still the same 2 servers running, but that instead of the DNS weight and routing being round-robin, we switch it so the primary node is the one serving traffic the majority of the time. The the secondary node is in passive mode, ready to accept and serve traffic if there's any issues with the primary node. This will require an alternative CNAME you would need to use. Please contact support if you require additional assistance, or have further questions about this.