Procedure 35.2. Setting Up Cross-Datacenter Replication

1. Configure the Local Site

   <infinispan
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="urn:infinispan:config:8.0 http://www.infinispan.org/schemas/infinispan-config-8.0.xsd"
         xmlns="urn:infinispan:config:8.0">
   
     <jgroups>
       <stack-file name="udp" path="jgroups-with-relay.xml"/>
     </jgroups>
   
     <cache-container default-cache="default">
       <transport cluster="infinispan-cluster" lock-timeout="50000" 
                  stack="udp" node-name="node1" 
                  machine="machine1" rack="rack1" site="LON"/>
         <local-cache name="default">
           <backups>
             <backup site="NYC" strategy="SYNC" failure-policy="IGNORE" timeout="12003"/>
             <backup site="SFO" strategy="ASYNC"/>
           </backups>
         </local-cache>
   
      <!-- Additional configuration information here -->
   </infinispan>

   1. Add the site attribute to the transport element to define the local site (in this example, the local site is named LON).
   2. Cross-site replication requires a non-default JGroups configuration. Define the jgroups element and define a custom stack-file, passing in the name of the file to be referenced and the location to this custom configuration. In this example, the JGroups configuration file is named jgroups-with-relay.xml.
   3. Configure the cache in site LON to back up to the sites NYC and SFO.
   4. Configure the back up caches:
      1. Configure the cache in site NYC to receive back up data from LON:

               <local-cache name="backupNYC">
                 <backups/>
                 <backup-for remote-cache="default" remote-site="LON"/>
               </local-cache>

      2. Configure the cache in site SFO to receive back up data from LON:

               <local-cache name="backupSFO">
                 <backups/>
                 <backup-for remote-cache="default" remote-site="LON"/>
               </local-cache>

2. Add the Contents of the Configuration File

   As a default, Red Hat JBoss Data Grid includes JGroups configuration files such as default-configs/default-jgroups-tcp.xml and default-configs/default-jgroups-udp.xml in the infinispan-embedded-{VERSION}.jar package.
   Copy the JGroups configuration to a new file (in this example, it is named jgroups-with-relay.xml) and add the provided configuration information to this file. Note that the relay.RELAY2 protocol configuration must be the last protocol in the configuration stack.

   <config> 
       ... 
       <relay.RELAY2 site="LON" 
                 config="relay.xml"
                 relay_multicasts="false" />
   </config>

3. Configure the relay.xml File

   Set up the relay.RELAY2 configuration in the relay.xml file. This file describes the global cluster configuration.

   <RelayConfiguration> 
       <sites> 
           <site name="LON" 
                 id="0"> 
               <bridges> 
                   <bridge config="jgroups-global.xml" 
                           name="global"/> 
                   </bridges> 
           </site>  
           <site name="NYC" 
                 id="1"> 
               <bridges> 
                   <bridge config="jgroups-global.xml" 
                           name="global"/> 
                   </bridges> 
           </site>  
           <site name="SFO" 
                 id="2"> 
               <bridges> 
                   <bridge config="jgroups-global.xml" 
                           name="global"/> 
               </bridges> 
           </site> 
       </sites> 
   </RelayConfiguration>

4. Configure the Global Cluster

   The file jgroups-global.xml referenced in relay.xml contains another JGroups configuration which is used for the global cluster: communication between sites.
   The global cluster configuration is usually TCP-based and uses the TCPPING protocol (instead of PING or MPING) to discover members. Copy the contents of default-configs/default-jgroups-tcp.xml into jgroups-global.xml and add the following configuration in order to configure TCPPING:

   <config> 
       <TCP bind_port="7800" ... /> 
       <TCPPING initial_hosts="lon.hostname[7800],nyc.hostname[7800],sfo.hostname[7800]"
                ergonomics="false" /> 
             <!-- Rest of the protocols --> 
   </config>

   Replace the hostnames (or IP addresses) in TCPPING.initial_hosts with those used for your site masters. The ports (7800 in this example) must match the TCP.bind_port.
   For more information about the TCPPING protocol, see Section 30.2.1.3, “Using the TCPPing Protocol”.