In this article we will see how to monitor server up or down status 
We will monitor HTTP, HTTPs servers, POP , SMTP servers, and FTP server.
Below is sample code which explain the rest. Each request send to monitor the server is online 5-6 line of code.
Add following code in to design view of your Default.aspx page
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server" Width="184px"></asp:TextBox>
<asp:DropDownList ID="DropDownList1" runat="server">
<asp:ListItem Value="110">POP</asp:ListItem>
<asp:ListItem Value="25">SMTP</asp:ListItem>
<asp:ListItem Value="80">HTTP</asp:ListItem>
<asp:ListItem Value="443">HTTPS</asp:ListItem>
<asp:ListItem Value="21">FTP</asp:ListItem>
<asp:ListItem Value="995">SSLPOP</asp:ListItem>
<asp:ListItem Value="465">SSLSMTP</asp:ListItem>
</asp:DropDownList><br />
<br />
<br />
<br />
<asp:Button ID="Button1" runat="server" OnClick="Button1_Click" Text="Button" /><br />
</div>
</form>
</body>
</html>
Add below code into code behind file of default.aspx page
*********************************************************************************************************
Default.aspx.cs
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
switch(DropDownList1.SelectedItem.Text)
{
case "POP" :
Monitor.ServerName = TextBox1.Text;
Monitor.Port = int.Parse(DropDownList1.SelectedValue);
Response.Write(Monitor.GetStreamResponse());
break;
case "HTTP" :
Response.Write(Monitor.GethttpResponse("http://" + TextBox1.Text));
break;
case "HTTPS" :
Response.Write(Monitor.GethttpResponse("https://" + TextBox1.Text));
break;
case "SMTP" :
Monitor.ServerName = TextBox1.Text;
Monitor.Port = int.Parse(DropDownList1.SelectedValue);
Response.Write(Monitor.GetStreamResponse());
break;
case "SSLPOP":
Monitor.ServerName = TextBox1.Text;
Monitor.Port = int.Parse(DropDownList1.SelectedValue);
Response.Write(Monitor.GetSecureStreamResponse());
break;
case "SSLSMTP":
Monitor.ServerName = TextBox1.Text;
Monitor.Port = int.Parse(DropDownList1.SelectedValue);
Response.Write(Monitor.GetSecureStreamResponse());
break;
}
}
}
Add monitor.cs class in to your app_Code folder
***************************************************************************************************
Monitor.cs
using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;
using System.IO;
using System.Net;
using System.Net.Sockets;
using System.Net.NetworkInformation;
using System.Net.Security;
/// <summary>
/// Summary description for Monitor
/// </summary>
public class Monitor
{
private static string _serverName = string.Empty;
private static int _port = 0; // int.MinValue;
static TcpClient tcpclient = null;
static NetworkStream ns = null;
static SslStream sslstream = null;
static StreamReader reader ;
static StreamWriter writer ;
public static string ServerName
{
get { return _serverName; }
set { _serverName = value; }
}
public static Int32 Port
{
get { return _port; }
set { _port = value; }
}
public static string GetStreamResponse()
{
try
{
tcpclient = new TcpClient();
tcpclient.SendTimeout = 10000;
//DateTime start = DateTime.Now.TimeOfDay;
tcpclient.Connect(ServerName, Port);
ns = tcpclient.GetStream();
reader = new StreamReader(ns);
string response = reader.ReadLine();
//DateTime end = DateTime.Now.TimeOfDay;
return response;
}
catch (Exception ex)
{
reader.Close();
ns.Close();
tcpclient.Close();
return ex.Message;
}
finally
{
ns.Close();
tcpclient.Close();
}
}
public static string GetSecureStreamResponse()
{
try
{
tcpclient = new TcpClient();
tcpclient.SendTimeout = 10000;
tcpclient.Connect(ServerName, Port);
sslstream = new SslStream(tcpclient.GetStream());
sslstream.AuthenticateAsClient(ServerName);
reader = new StreamReader(sslstream);
string str = reader.ReadLine();
return str;
}
catch (Exception ex)
{
reader.Close();
return ex.Message;
}
finally
{
sslstream.Close();
tcpclient.Close();
}
}
public static string GethttpResponse(string domainName)
{
try
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(domainName);
request.Timeout = 10000;
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
string str = response.StatusCode.ToString();
response.Close();
return str;
}
catch (Exception ex)
{
return ex.Message;
}
}
}
-Satalaj