:fix: add comments to broker.xml related to clusterization

Signed-off-by: riccardomodanese <[email protected]>

assembly/broker-artemis/configurations/broker.xml

@@ -91,6 +91,18 @@
         -->
         <!-- allowLinkStealing=true -->
 
+        <!-- CLUSTER CONFIGURATION NOTES -->
+        <!-- The current Kapua deployment deploys a broker with 2 consumers (Lifecycle and Telemetry) plus the Authentication service.
+             If a cluster is needed, the following steps could be followed:
+                - change the run-broker script, section "/opt/artemis/bin/artemis create \", (of the broker container) to create the cluster simply adding "-clustered" option and changing cluster username and password.
+                  (see https://activemq.apache.org/components/artemis/documentation/latest/using-server.html#creating-a-broker-instance)
+                - change this configuration file adding the cluster connectors as per cluster topology
+                  (see https://activemq.apache.org/components/artemis/documentation/latest/clusters.html)
+                - change the consumer/service connection string according to the documentation
+                  (see section 3.2.2 of the link https://activemq.apache.org/components/artemis/documentation/latest/clusters.html)
+             NOTE: The consumers/service could be scaled up also and independently each from the others.
+             IMPORTANT NOTE: while clustering pay attention to the performances as described in chapter 2 of the link https://activemq.apache.org/components/artemis/documentation/latest/clusters.html.
+        -->
         <!-- disable caching at all, otherwise we'll have issues while managing stealing link:
             the remove connection (ServerPlugin#afterDestroyConnection) is called without calling the authenticate (SecurityPlugin#authenticate).
         TODO do further tests to check the performance impact and try to enable authorization cache only -->