Did you set up remote events between X and Y?

No I did not. I'll look into it

is it this? From url http://world.episerver.com/documentation/Items/Developers-Guide/Episerver-CMS/9/Event-management/WCF-event-management/

<system.serviceModel>
...
    <services>
       <service name="[IIS web site name 1]/EPiServer.Events.Remote.EventReplication" 
                 behaviorConfiguration="*">
           <endpoint name="RemoteEventServiceEndPoint" 
                     contract="EPiServer.Events.ServiceModel.IEventReplication"
                     binding="*" address="*" />
       </service>
    </services>

       <service name="[IIS web site name 2]/EPiServer.Events.Remote.EventReplication" 
                 behaviorConfiguration="*">
           <endpoint name="RemoteEventServiceEndPoint" 
                     contract="EPiServer.Events.ServiceModel.IEventReplication"
                     binding="*" address="*" />
       </service>
    </services>
...
 </system.serviceModel>

Yes.

So if server X has IP address 192.168.1.1. and server Y has IP address 192.182.1.2, and they both communicate with each other on port 5000, you should have

<services>
	<service name="EPiServer.Events.Remote.EventReplication">
	<endpoint
		name="RemoteEventServiceEndPoint"
		contract="EPiServer.Events.ServiceModel.IEventReplication"
		bindingConfiguration="RemoteEventsBinding"
		address="net.tcp://192.168.1.1:5000/RemoteEventService"
		binding="netTcpBinding" />
	</service>
</services>
<client>
<endpoint name="Y"
	address="net.tcp://192.168.1.2:5000/RemoteEventService"
	binding="netTcpBinding"
	bindingConfiguration="RemoteEventsBinding"
	contract="EPiServer.Events.ServiceModel.IEventReplication" />
</client>

On server X.

And 

<services>
	<service name="EPiServer.Events.Remote.EventReplication">
	<endpoint
		name="RemoteEventServiceEndPoint"
		contract="EPiServer.Events.ServiceModel.IEventReplication"
		bindingConfiguration="RemoteEventsBinding"
		address="net.tcp://192.168.1.2:5000/RemoteEventService"
		binding="netTcpBinding" />
	</service>
</services>
<client>
<endpoint name="X"
	address="net.tcp://192.168.1.1:5000/RemoteEventService"
	binding="netTcpBinding"
	bindingConfiguration="RemoteEventsBinding"
	contract="EPiServer.Events.ServiceModel.IEventReplication" />
</client>

On server Y.

Episerver cashes data for performance reasons. Remote events are used to notify the clients when data has changed so that they can invalidate the cache.

hey Dejan

The webconfig is shared between x and y.  literally both boxes point to the same file share to run their own instances of the website.  Is this not a good way to do the deployment?

You can have several web servers that use the same database and blob storage in a load-balanced environment, but web.config files cannot be identical because you need to have different remote events settings for each one of them.

Server X needs to send remote events to server Y. And server Y needs to send remote events to server X.

If you add additional server, Z, then

X should send remote events to Y and Z.

Y should send remote events to X and Z

and so on...

You would typically solve this using config transformations during deploy.