# Correct value for jgroups external\_addr value when running KC 16.x in Docker Swarm **URL:** \ **Category:** Configuring the server\ **Created:** [March 6, 2022, 11:57pm UTC](https://forum.keycloak.org/t/correct-value-for-jgroups-external-addr-value-when-running-kc-16-x-in-docker-swarm/14076 "2022-03-06T23:57:52Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![the-dude](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/the-dude/32/5033_2.png) [@the-dude](https://forum.keycloak.org/u/the-dude)\ **Post date:** [March 6, 2022, 11:57pm UTC](https://forum.keycloak.org/t/correct-value-for-jgroups-external-addr-value-when-running-kc-16-x-in-docker-swarm/14076/1 "2022-03-06T23:57:53Z")
Hello, I am stuck trying to set the proper jgroups configuration for a clustered standalone installation of KC: ```auto /subsystem=jgroups/stack=tcp/transport=TCP/property=external_addr:add(value=${env.JGROUPS_DISCOVERY_EXTERNAL_IP}) ``` I have 3 Docker Swarm host machines on EC2, each running potentially more than 1 KC container, to what value should I set the jgroup external\_addr configuration of each container? Does the value need to be unique per KC instance which is my understanding so far **or** can 2 instances running on the same host announce the same external\_addr - such as the internal EC2 IP/hostname? If the value needs to be unique what should I use in my scenario - I was thinking : `JGROUPS_DISCOVERY_EXTERNAL_IP : {{.Task.Name}}` Thanks, David ---
**Author:** ![the-dude](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/the-dude/32/5033_2.png) [@the-dude](https://forum.keycloak.org/u/the-dude)\ **Post date:** [March 7, 2022, 5:29pm UTC](https://forum.keycloak.org/t/correct-value-for-jgroups-external-addr-value-when-running-kc-16-x-in-docker-swarm/14076/2 "2022-03-07T17:29:23Z")
Hello, I have tried both strategies to no avail: - Setting `JGROUPS_DISCOVERY_EXTERNAL_IP` to `{{.Task.Name}}` - making sure tasks can ping each other - Modifying docker-entrypoint.sh to set `JGROUPS_DISCOVERY_EXTERNAL_IP` to the EC2 internal IP address something like: `ip-172-xx-xx-xxx.eu-west-3.compute.internal` Do these need to be actual IPs not hostnames? **Neither** strategy results in an Infispan cluster being created between nodes as per logs: ```auto # I expect to see several nodes here... 13:13:21,135 INFO [org.infinispan.CLUSTER] (ServerService Thread Pool -- 56) ISPN000094: Received new cluster view for channel ejb: [699ec079bb5e|0] (1) [699ec079bb5e] ``` In addition I have added JDBC\_PING.cli from an official [blog post](https://www.keycloak.org/2019/05/keycloak-cluster-setup.html) on the subject to my image since by looking at the KC 16.x Dockerfile repository I noticed that this setting is not being taking into account to set external\_addr for the Infinispan discovery. Has anyone actually gotten JDBC\_PING to work using Docker Swarm as an orchestrator? If so a concrete example would be appreciated. For what it’s worth I do see some join attempts (regardless of specifying JGROUPS\_DISCOVERY\_EXTERNAL\_IP) but they fail: ```auto 18:26:31,151 WARN [org.jgroups.protocols.pbcast.GMS] (ServerService Thread Pool -- 56) 7a122481a7f2: JOIN(7a122481a7f2) sent to 70c8446ec082 timed out (after 3000 ms), on try 8 ``` Best regards, David ---
**Author:** ![the-dude](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/the-dude/32/5033_2.png) [@the-dude](https://forum.keycloak.org/u/the-dude)\ **Post date:** [March 8, 2022, 12:05am UTC](https://forum.keycloak.org/t/correct-value-for-jgroups-external-addr-value-when-running-kc-16-x-in-docker-swarm/14076/3 "2022-03-08T00:05:02Z")
Ok, for anyone coming through here, in the end I set the `BIND: "{{.Task.Name}}"` environment variable in the compose file I use on Docker Swarm. This seems to do the trick, I see the Infinispan cluster forming. I believe the issue was something to do with binding adresses used by JGroups and/or Wildfly, possibly similar to what was discued [here](http://forum.keycloak.org/t/jgroups-tcp-timeout-in-aws-ecs/9726/2). I do not have to set `JGROUPS_DISCOVERY_EXTERNAL_IP` in the end from what I see. I did not change/add parameters from the repository [example](https://github.com/keycloak/keycloak-containers/blob/16.1.1/docker-compose-examples/keycloak-postgres-jdbc-ping.yml) apart from the the deploy part for Docker Swarm. /David ---
**Author:** ![dasniko](https://yyz2.discourse-cdn.com/free1/user_avatar/forum.keycloak.org/dasniko/32/2969_2.png) [@dasniko](https://forum.keycloak.org/u/dasniko)\ **Post date:** [March 8, 2022, 6:23am UTC](https://forum.keycloak.org/t/correct-value-for-jgroups-external-addr-value-when-running-kc-16-x-in-docker-swarm/14076/4 "2022-03-08T06:23:15Z")
This helped me one time: [Adventures with Docker Swarm and Keycloak Clustering](http://forum.keycloak.org/t/adventures-with-docker-swarm-and-keycloak-clustering/6702)