public void forceDisconnect() {
    vm.invoke("force disconnect", () -> ClusterStartupRule.memberStarter.forceDisconnectMember());
  }
this disconnects the distributed system of the member. The member will automatically try to
reconnect after 5 seconds.
geode-dunit/src/main/java/org/apache/geode/test/dunit/rules/MemberVM.java