protected void requestNeighbors(
      final MockPeerDiscoveryAgent fromAgent, final MockPeerDiscoveryAgent toAgent) {
    final FindNeighborsPacketData data =
        packetPackage.findNeighborsPacketDataFactory().create(Peer.randomId());
    final Packet packet =
        packetPackage
            .packetFactory()
            .create(PacketType.FIND_NEIGHBORS, data, fromAgent.getNodeKey());
    helper.sendMessageBetweenAgents(fromAgent, toAgent, packet);
  }
These tests simulates the case where a node crashes then comes back up with a new ip address or
listening port.
ethereum/p2p/src/test/java/org/hyperledger/besu/ethereum/p2p/discovery/PeerDiscoveryAgentTest.java