[SNMP4J] Problems with sending SNMP traps to IP addres that is not localhost (127.0.0.1)

[Ivan Mladenović]

I'm trying to send snmp V2 trap from my java code. Everything works fine
when both (manager and agent) are on localhost,
but if I try to send a trap to manager that is on another machine, I don't
receive any traps. If I use some other program
for generating traps (for example "SNMP trap stormer" from AdventNet
simulation toolkit 7) I don't have this issue.

Here is my code:
 void confgure() throws UnknownHostException, IOException {
  // Create the Manager address
  UdpAddress managerUdpAddress = new
UdpAddress(InetAddress.getByName(managerHost), managerPort);
  // works fine when manager host="127.0.0.1"
  // Create the Agent address
  UdpAddress agentUdpAddress = new
UdpAddress(InetAddress.getByName(agentHost), agentPort);

  // Create the Community Target using the manager address
  ctarget = new CommunityTarget(managerUdpAddress, new
OctetString(community));
  ctarget.setCommunity(new OctetString(community));
  ctarget.setRetries(retries);
  ctarget.setTimeout(timeout);

  // Create the Transport Mapping using the agent address
  ctransport = new DefaultUdpTransportMapping(agentUdpAddress);
  // Create the session object
  snmp = new Snmp(ctransport);
 }

....
sending trap:

public void sendV2Trap(String trapOid, String message) throws Exception {

  long sysUpTime = (System.currentTimeMillis() / 10) - startTime;
  sysUpTime = sysUpTime % MAX_SYSUPTIME;
  // Set SNMP version as V2
  ctarget.setVersion(SnmpConstants.version2c);
  // Create trap with time ticks, the trap OID and the message
  PDU trapPdu = new PDU();

  trapPdu.add(new VariableBinding(new OID(SYS_UP_TIME), new
TimeTicks(sysUpTime)));
  trapPdu.add(new VariableBinding(new OID(SNMP_TRAP_OID), new
OID(trapOid)));
  trapPdu.add(new VariableBinding(new OID(trapOid), new
OctetString(message.getBytes())));

  // Send trap
  snmp.notify(trapPdu, ctarget);
 }


P.S. To view received traps, I use Trap Receiver (
http://www.trapreceiver.com/)