How to isolate elastic search node from other nodes?

Hello,

I have some integration test of my application. The integration test starts own elastic search instance by
node = nodeBuilder().settings(settings).local(true).node();
and do its job.

However, I have other, running elastic search instance on my computer. I observed that runnich elastic search instance and integration test instance establish a connection (because I see IO exception in running ES log when integration test is terminated)

My question is: how to configure ES for integration test to make sure it is isolated against any other working ES in my computer/LAN?

I tried settings
.put("multicast.enabled","false")
.put("discovery.zen.ping.multicast.ping.enabled", "false")

but without success

best regards
Michal Domagala