Generating TRAP in SNMP using SNMP4j

As we have discussed, Traps are like events. This is a way the SNMP agent pushes the information to client. Asynchronously, events can be fired to client from server (agent).

Example:

SNMP Trap Receiver:

package com.G2.SNMP.Trap.receiver;

import java.io.IOException;

import org.snmp4j.CommandResponder;
import org.snmp4j.CommandResponderEvent;
import org.snmp4j.CommunityTarget;
import org.snmp4j.MessageDispatcher;
import org.snmp4j.MessageDispatcherImpl;
import org.snmp4j.MessageException;
import org.snmp4j.PDU;
import org.snmp4j.Snmp;
import org.snmp4j.mp.MPv1;
import org.snmp4j.mp.MPv2c;
import org.snmp4j.mp.StateReference;
import org.snmp4j.mp.StatusInformation;
import org.snmp4j.security.Priv3DES;
import org.snmp4j.security.SecurityProtocols;
import org.snmp4j.smi.OctetString;
import org.snmp4j.smi.TcpAddress;
import org.snmp4j.smi.TransportIpAddress;
import org.snmp4j.smi.UdpAddress;
import org.snmp4j.transport.AbstractTransportMapping;
import org.snmp4j.transport.DefaultTcpTransportMapping;
import org.snmp4j.transport.DefaultUdpTransportMapping;
import org.snmp4j.util.MultiThreadedMessageDispatcher;
import org.snmp4j.util.ThreadPool;

public class TrapReceiver implements CommandResponder {
	public static void main(String[] args) {
		TrapReceiver snmp4jTrapReceiver = new TrapReceiver();
		try {
			snmp4jTrapReceiver.listen(new UdpAddress("localhost/162"));
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

	/**
	 * Trap Listner
	 */
	public synchronized void listen(TransportIpAddress address)
			throws IOException {
		AbstractTransportMapping transport;
		if (address instanceof TcpAddress) {
			transport = new DefaultTcpTransportMapping((TcpAddress) address);
		} else {
			transport = new DefaultUdpTransportMapping((UdpAddress) address);
		}

		ThreadPool threadPool = ThreadPool.create("DispatcherPool", 10);
		MessageDispatcher mDispathcher = new MultiThreadedMessageDispatcher(
				threadPool, new MessageDispatcherImpl());

		// add message processing models
		mDispathcher.addMessageProcessingModel(new MPv1());
		mDispathcher.addMessageProcessingModel(new MPv2c());

		// add all security protocols
		SecurityProtocols.getInstance().addDefaultProtocols();
		SecurityProtocols.getInstance().addPrivacyProtocol(new Priv3DES());

		// Create Target
		CommunityTarget target = new CommunityTarget();
		target.setCommunity(new OctetString("public"));

		Snmp snmp = new Snmp(mDispathcher, transport);
		snmp.addCommandResponder(this);

		transport.listen();
		System.out.println("Listening on " + address);

		try {
			this.wait();
		} catch (InterruptedException ex) {
			Thread.currentThread().interrupt();
		}
	}

	/**
	 * This method will be called whenever a pdu is received on the given port
	 * specified in the listen() method
	 */
	public synchronized void processPdu(CommandResponderEvent cmdRespEvent) {
		System.out.println("Received PDU...");
		PDU pdu = cmdRespEvent.getPDU();
		if (pdu != null) {
			System.out.println("Trap Type = " + pdu.getType());
			System.out.println("Variables = " + pdu.getVariableBindings());
			}
		}
	}

Version 1 Trap Sender:

package com.G2.SNMP.Trap.Sender;

import org.snmp4j.CommunityTarget;
import org.snmp4j.PDU;
import org.snmp4j.PDUv1;
import org.snmp4j.Snmp;
import org.snmp4j.TransportMapping;
import org.snmp4j.mp.SnmpConstants;
import org.snmp4j.smi.IpAddress;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.OctetString;
import org.snmp4j.smi.UdpAddress;
import org.snmp4j.transport.DefaultUdpTransportMapping;

public class TrapSenderVersion1 {

	public static final String community = "public";

	// Sending Trap for sysLocation of RFC1213
	public static final String Oid = ".1.3.6.1.2.1.1.8";

	//IP of Local Host
	public static final String ipAddress = "127.0.0.1";

	//Ideally Port 162 should be used to send receive Trap, any other available Port can be used
	public static final int port = 162;

	public static void main(String[] args) {
		TrapSenderVersion1 trapV1 = new TrapSenderVersion1();
		trapV1.sendTrap_Version1();
	}
	/**
	 * This methods sends the V1 trap to the Localhost in port 162
	 */
	public void sendTrap_Version1() {
		try {
			// Create Transport Mapping
			TransportMapping transport = new DefaultUdpTransportMapping();
			transport.listen();

			// Create Target
			CommunityTarget cTarget = new CommunityTarget();
			cTarget.setCommunity(new OctetString(community));
			cTarget.setVersion(SnmpConstants.version1);
			cTarget.setAddress(new UdpAddress(ipAddress + "/" + port));
			cTarget.setTimeout(5000);
			cTarget.setRetries(2);

			PDUv1 pdu = new PDUv1();
			pdu.setType(PDU.V1TRAP);
			pdu.setEnterprise(new OID(Oid));
			pdu.setGenericTrap(PDUv1.ENTERPRISE_SPECIFIC);
			pdu.setSpecificTrap(1);
			pdu.setAgentAddress(new IpAddress(ipAddress));

			// Send the PDU
			Snmp snmp = new Snmp(transport);
			System.out.println("Sending V1 Trap... Check Wheather NMS is Listening or not? ");
			snmp.send(pdu, cTarget);
			snmp.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}

Output:

Listening on 127.0.0.1/162
Received PDU…
Trap Type = -92
Variables = []

Version 2 Trap Sender:

package com.G2.SNMP.Trap.Sender;

import java.util.Date;

import org.snmp4j.CommunityTarget;
import org.snmp4j.PDU;
import org.snmp4j.Snmp;
import org.snmp4j.TransportMapping;
import org.snmp4j.mp.SnmpConstants;
import org.snmp4j.smi.IpAddress;
import org.snmp4j.smi.OID;
import org.snmp4j.smi.OctetString;
import org.snmp4j.smi.UdpAddress;
import org.snmp4j.smi.VariableBinding;
import org.snmp4j.transport.DefaultUdpTransportMapping;

public class TrapSenderVersion2 {

	public static final String community = "public";

	// Sending Trap for sysLocation of RFC1213
	public static final String Oid = ".1.3.6.1.2.1.1.8";

	//IP of Local Host
	public static final String ipAddress = "127.0.0.1";

	//Ideally Port 162 should be used to send receive Trap, any other available Port can be used
	public static final int port = 162;

	public static void main(String[] args) {
		TrapSenderVersion2 trapV2 = new TrapSenderVersion2();
		trapV2.sendTrap_Version2();
	}
	/**
	 * This methods sends the V1 trap to the Localhost in port 162
	 */
	public void sendTrap_Version2() {
		try {
			// Create Transport Mapping
			TransportMapping transport = new DefaultUdpTransportMapping();
			transport.listen();

			// Create Target
			CommunityTarget cTarget = new CommunityTarget();
			cTarget.setCommunity(new OctetString(community));
			cTarget.setVersion(SnmpConstants.version2c);
			cTarget.setAddress(new UdpAddress(ipAddress + "/" + port));
			cTarget.setRetries(2);
			cTarget.setTimeout(5000);

			// Create PDU for V2
			PDU pdu = new PDU();

			// need to specify the system up time
			pdu.add(new VariableBinding(SnmpConstants.sysUpTime,
					new OctetString(new Date().toString())));
			pdu.add(new VariableBinding(SnmpConstants.snmpTrapOID, new OID(
					Oid)));
			pdu.add(new VariableBinding(SnmpConstants.snmpTrapAddress,
					new IpAddress(ipAddress)));

			pdu.add(new VariableBinding(new OID(Oid), new OctetString(
					"Major")));
			pdu.setType(PDU.NOTIFICATION);

			// Send the PDU
			Snmp snmp = new Snmp(transport);
			System.out.println("Sending V2 Trap... Check Wheather NMS is Listening or not? ");
			snmp.send(pdu, cTarget);
			snmp.close();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}

Output:

Listening on 127.0.0.1/162
Received PDU…
Trap Type = -89
Variables = [1.3.6.1.2.1.1.3.0 = Wed Feb 16 01:17:02 IST 2011, 1.3.6.1.6.3.1.1.4.1.0 = 1.3.6.1.2.1.1.6, 1.3.6.1.6.3.18.1.3.0 = 127.0.0.1, 1.3.6.1.2.1.1.6 = Major]