Merge pull request #778 from FusionAuth/add-plugins-to-cluster

Added note about plugins.

Author: mooreds

site/docs/v1/tech/installation-guide/cluster.adoc

@@ -46,6 +46,7 @@ When building a FusionAuth cluster, consider:
 * What level of security and network isolation do you need? Build the architecture that suits your needs. You can run FusionAuth in a private network and have all HTTP connections proceed through the load balancer, with SSH connections happening through a jump box, for example.
 * What version of FusionAuth will you be running? All nodes must be on the same version for correct functionality.
 * How will you manage link:/docs/v1/tech/reference/configuration/[FusionAuth configuration]? All nodes must have the same configuration or undetermined behavior will occur. Ensure that configuration changes are replicated to every node.
+* Will you use a custom password hashing plugin? If so, plan to distribute the plugin to every node, distribute to a shared filesystem, or otherwise make it available.
 * With a standalone database you must use the link:/docs/v1/tech/installation-guide/fusionauth-app/#advanced-installation[advanced database installation] and run the database creation and migration scripts outside of FusionAuth. How will you manage this? Do you have in-house tools you can leverage to do so?
 
 === FusionAuth Installation
@@ -62,7 +63,7 @@ Build your link:/docs/v1/tech/reference/configuration/[FusionAuth configuration]
 * Set `database.username` to the database user name recorded above.
 * Update `database.password` as the database password noted above.
 
-Distribute your FusionAuth configuration to all nodes. They must all have the same configuration. You can do this by setting environment variables, Java system properties, or by pushing the `fusionauth.properties` file to each server. 
+Distribute your FusionAuth configuration to all nodes. They must all have the same configuration. You can do this by setting environment variables, Java system properties, or by pushing the `fusionauth.properties` file to each server. If you have a password hashing plugin, make sure it is distributed or available to all the nodes as well.
 
 Restart the instances to ensure configuration changes are picked up.
 
@@ -129,6 +130,7 @@ To add more nodes to the cluster, do the following:
 
 * Stand up new FusionAuth servers.
 * Provide the same FusionAuth configuration as the existing nodes. In particular, provide the same connection info for the database. 
+* Add any custom password hashing plugins, if used. You can either use a shared filesystem or copy the plugin jar file to the correct location.
 * Update your load balancer to send traffic to the new node.
 
 To remove nodes, simply: