Wildfly 10 Add Load Balancer to existing domain

Question

I have no prior experience with Wildfly or JBOSS before implementing this scenario. I have Wildfly 10 running in Domain mode. 2 hosts each running 1 wildfly server connected to a single datasource. Server1 -Master- Domain Controller Server2 - Slave The Datasource is configured under the "DEFAULT" Profile The Deployment is under the "FULL" profile.

I now need to add a load balancing into the equation but I only want to use Wildfly. I have read the following article to set up a Static Load balncer as a reverse proxy https://docs.jboss.org/author/display/WFLY10/Using+Wildfly+as+a+Load+Balancer

I have a 3rd Server that I want to configure as the Load Balancer. Do I configure this as a "SLAVE" in the domain but add it to the LOAD-BALANCER Profile on the Domain Controller? When I do this, it cannot find and connect to the Master (Server1)!

Please can someone tell me the basic set up I need to have on this server for me to be in a position to follow the steps in the above article and configure it as a reverse-proxy/static load balancer?

Many Thanks

Answer 1

If you wish to use wildfly as load balancer with modcluster/static load balancing configuration, then you don't need to include the server (which will act as load balancer) in cluster/domain. You can separaty invoke the load balancer server. Wildfly10 distribution has already one example file - standalone-load-balancer.xml (inside - \docs\examples\configs), which can be used directly.

This file is having minimum configuration required for using wildfly 10.1 as load balancer.

Once the server is up using that file, it will automatically discovers the worker nodes that are participating in clustering (provided multicast address and ports are working and accessible in the network).

Also please note that all worker nodes should have different node name otherwise if some nodes lie on the same machine and if they are not invoked with different node names then they may get rejected by the load balancer server.

Below is the command to invoke the wildfly server with specific node name ---

standalone.bat -Djboss.node.name=<specify the node name here>

Basic setup will be like below --

[1] Invoke the two separate nodes (wildfly instance) with configuration - standalone-ha.xml/standalone-full-ha.xml with some web-app (e.g. cluster-demo.war). Please note that deployment descriptor of web application must have tag inside it, otherwise cluster will not get set up after the invocation of two worker nodes.

[2] After success of 1st step, user can see message - received new cluster view in console log of worker nodes.

[3] LOAD BALANCER CONFIGURATION --

[3.1] DYNAMIC LOAD BALANCER (using modcluser configuration)--------

Invoke the third instance of wildfly with configuration - standalone-load-balancer.xml

If load balancer detects all the worker nodes then user will see the log message - registering node - nodeName, in console log of load balancer server.

[3.2] STATIC LOAD BALANCER CONFIGURATION -----

cli---

/subsystem=undertow/configuration=handler/reverse-proxy=my-handler1:add()

/socket-binding-group=standard-sockets/remote-destination-outbound-socket-binding=remote-host111/:add(host=localhost, port=9080) /socket-binding-group=standard-sockets/remote-destination-outbound-socket-binding=remote-host222/:add(host=localhost, port=10080)

/subsystem=undertow/configuration=handler/reverse-proxy=my-handler1/host=host11:add(outbound-socket-binding=remote-host111, scheme=http, instance-id=cluster-demoroute, path=/cluster-demo) /subsystem=undertow/configuration=handler/reverse-proxy=my-handler1/host=host22:add(outbound-socket-binding=remote-host222, scheme=http, instance-id=cluster-demoroute, path=/cluster-demo)

/subsystem=undertow/server=default-server/host=default-host/location=/cluster-demo:add(handler=my-handler1)

configuration replacement-------------

[A] Add below reverse-proxy tag inside subsystem-undertow/handlers tag--

<reverse-proxy name="my-handler1">
                    <host name="host11" outbound-socket-binding="remote-host111" path="/cluster-demo" instance-id="cluster-demoroute"/>
                    <host name="host22" outbound-socket-binding="remote-host222" path="/cluster-demo" instance-id="cluster-demoroute"/>
                </reverse-proxy>

[B] Add location tag inside subsystem - undertow/server=default-server/default-host

<location name="/cluster-demo" handler="my-handler1"/>

[C] Add below inside socket-binding-group tag

<outbound-socket-binding name="remote-host111">
            <remote-destination host="localhost" port="9080"/>
        </outbound-socket-binding>
        <outbound-socket-binding name="remote-host222">
            <remote-destination host="localhost" port="10080"/>
        </outbound-socket-binding>