Secured Connection Between SQL Server and C# Using Specific Port

Introduction

A few days ago, I experienced a situation in which my client needed to shift his database server to a static IP. This choice makes the database server very insecure. So we decided to close all our unnecessary ports on the router. After closing the unnecessary ports, connections between C# and SQL Server creates problems. We even tried to use the default port of SQL Server, 1433, but it's not working because we are not using a default instance of the SQL Server.

In this article, we will discuss how to get the port number of our SQL Server instance and how to use that port in a SQL Server setting, and at the end, how to use that port in your C# application.

Step 1

We are assuming that we have installed SQL Server with the instance name CRMIS and first of all, we need to find the specific port of that instance using regedit.

So click on "Start" -> "Run," enter "regedit" and click "Ok." Then in the Registry Editor, navigate to.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MicrosoftSQLServer\MSSQL.<InstanceNumber>\MSSQLServer\SuperSocketNetLib\TCP\

Step 2

In this step, we will click "Start" - > "Programs" -> "Microsoft SQL Server 2005" -> "Configuration Tools" -> "SQL Configuration Manager."

Step 3

In this step, we will select CRMIS from the left window and double-click on TCP/IP. That will open TCP/IP Properties.

From the TCP/IP windows, select the IP Addresses table as shown in the following picture.

Select the IP ALL property from the IP Addresses and enter the port number in front of the TCP Dynamic Port, as shown in the picture.

Step 4

In this step, we will create a new C# Application to build the connection between C# and SQL Server using a specific port. Our project name is "Specific port," as shown in the following picture.

Step 5

In this section, we will create a new class with the name "Operation" using "Project" -> "Add class," as shown in the picture.

Now we will add code for the class Operation. This looks like. Please note that we have created a text file named "IPCONFG.txt." We can pass an IP address and port number to our connection string using that file.

Step 6

This section will add the following code to the program class.

Step 7

Now add the label on Frmlogin and the text on Connection Build Successfully.

Step 8

Press F5 to execute the program.