I found An assembly called snmpsharpnet wich is very helpful to play with SNMP on the top of .NET.
According to the explanation I wrote in this article the rate of input bandwith usage can be computed by for agiven interface:
"In" Bandwith usage in % = (((ifInOctets(t2)-ifInOctets(t1)) * 8)*100) / (ifSpeed * (t2-t1))
Here is a sample code.
using System;
using System.Collections.Generic;
using System.Text;
using SnmpSharpNet;
namespace Exemple2
{
class Program
{
static void Main(string[] args)
{
/* Get an SNMP Object
*/
SimpleSnmp snmpVerb = new SimpleSnmp("192.168.1.121", 161, "public");
if (!snmpVerb.Valid)
{
Console.WriteLine("Seems that IP or comunauty is not cool");
return;
}
/* Sample of simple Get usage on ifSpeed on interface 10
* TODO : for sure you have to detect the right interface
*/
Oid oidifSpeed = new Oid(".1.3.6.1.2.1.2.2.1.5.10");
/* Getting ifSpeed
*/
Dictionary<Oid, AsnType> snmpDataS = snmpVerb.Get(SnmpVersion.Ver2, new string[] { oidifSpeed.ToString() });
if (snmpDataS != null)
Console.WriteLine("Interface speed \"{0}\" : {1}", oidifSpeed.ToString(), snmpDataS[oidifSpeed].ToString());
else
Console.WriteLine("Not Glop!");
/* Sample of simple Get usage on ifInOctets on interface 10
* TODO : for sure you have to detect the right interface
*/
Oid oidifInOctets = new Oid(".1.3.6.1.2.1.2.2.1.10.10");
Dictionary<Oid, AsnType> snmpData1;
/* Getting it for the first time
*/
snmpData1 = snmpVerb.Get(SnmpVersion.Ver2, new string[] { oidifInOctets.ToString() });
if (snmpData1 != null)
Console.WriteLine("Number of In octets \"{0}\" : {1}", oidifInOctets.ToString(), snmpData1[oidifInOctets].ToString());
else
Console.WriteLine("Not Glop!");
int missed = 0;
while (true)
{
if (missed == 0)
{
/* When you detect a non refesh data, keep the last one
*/
snmpData1 = snmpVerb.Get(SnmpVersion.Ver2, new string[] { oidifInOctets.ToString() });
if (snmpData1 != null)
Console.WriteLine("Number of In octets \"{0}\" : {1}", oidifInOctets.ToString(), snmpData1[oidifInOctets].ToString());
else
Console.WriteLine("Not Glop!");
}
/* Some Wait (less aproximative)
*/
int duration = 5;
System.Threading.Thread.Sleep(duration*1000); // duration seconds
/* Getting it for the Second time
*/
Dictionary<Oid, AsnType> snmpData2 = snmpVerb.Get(SnmpVersion.Ver2, new string[] { oidifInOctets.ToString() });
if (snmpData2 != null)
Console.WriteLine("Number of In octets \"{0}\" : {1}", oidifInOctets.ToString(), snmpData2[oidifInOctets].ToString());
else
Console.WriteLine("Not Glop!");
Counter32 I1 = new Counter32();
I1.Set(snmpData1[oidifInOctets]);
Counter32 I2 = new Counter32();
I2.Set(snmpData2[oidifInOctets]);
Counter32 speed = new Counter32();
speed.Set(snmpDataS[oidifSpeed]);
if (I2.Value == I1.Value)
{
missed += 1;
continue;
}
decimal bandWithUsage = (((decimal)(I2.Value - I1.Value) * 8) * 100) / (speed * duration * (1+missed));
Console.WriteLine("BandWith usage : {0}%", bandWithUsage);
missed = 0;
}
}
}
}
This is just au proof of concept, now you probably need to incoparate a BackgroundWorker and a timer.
If you are not sure if SNMP is joignable on the server and you want to test the SNMP port connection, you will need Microsoft PortQry. This tool determines if the port is listening. This tool also provides additional functionality, depending on the command you use.