Docker-compose file to demonstrate the (tentative) failure of JGroups in Keycloak 9.0.0

docker-compose.yml

version: '3'

volumes:
  postgres_data:
      driver: local

services:
  postgres:
      image: postgres
      environment:
        POSTGRES_DB: keycloak
        POSTGRES_USER: keycloak
        POSTGRES_PASSWORD: password
      networks: [keycloak]
  keycloak1:
      image: quay.io/keycloak/keycloak:latest
      environment:
        DB_VENDOR: POSTGRES
        DB_ADDR: postgres
        DB_DATABASE: keycloak
        DB_USER: keycloak
        DB_SCHEMA: public
        DB_PASSWORD: password
        KEYCLOAK_USER: admin
        KEYCLOAK_PASSWORD: Pa55w0rd
        JGROUPS_DISCOVERY_PROTOCOL: TCPPING
      ports:
        - 8080:8080
      depends_on:
        - postgres
      networks: [keycloak]
  keycloak2:
      image: quay.io/keycloak/keycloak:latest
      entrypoint:
        - bash
        - -c
        - "sleep 30s && /opt/jboss/tools/docker-entrypoint.sh -b 0.0.0.0"
      command: ""
      environment:
        DB_VENDOR: POSTGRES
        DB_ADDR: postgres
        DB_DATABASE: keycloak
        DB_USER: keycloak
        DB_SCHEMA: public
        DB_PASSWORD: password
        KEYCLOAK_USER: admin
        KEYCLOAK_PASSWORD: Pa55w0rd
        JGROUPS_DISCOVERY_PROTOCOL: TCPPING
        JGROUPS_DISCOVERY_PROPERTIES: initial_hosts=keycloak1[8080]
      ports:
        - 8081:8080
      depends_on:
        - postgres
      networks: [keycloak]

networks:
  keycloak: