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DNS Server Configuration on CentOS 7 (Caching DNS with BIND)
DNS (Domain Name System) Server is an essential part to any computer network. Today web communication cannot imagine without DNS Server. DNS is a client server protocol where DNS Client requests for the domain name resolution and DNS Server response on it. Every network should have a DNS Server because local DNS Server improves network performance by caching DNS information and serving DNS request locally. DNS Server can be configured either Windows or Linux operating system. In this article, I will discuss how to configure a caching DNS Server on CentOS 7/ RedHat 7 Linux with BIND9 Service. Domain Name System (DNS) and How It Works Communication between a workstation (PC) and a Server are always done by IP address. So, to get any information from any Web Server, you have to remember the IP address of that Server. But remembering a huge number of public IP addresses is almost impossible for the human being. To solve this issue, DNS technique is introduced in computer networking. The DNS technique can be best compared to a phone book where a user finds a phone number listed by the easier-to-remember name. So, the DNS can be defined as a mapper between human [...]
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MikroTik Hotspot Auto Login by MAC Address | July 1, 2020
Hotspot is an awesome service in MikroTik Router. MikroTik Hotspot is popularly used in ISP, Hotel, Airport, Coffee Shop, Enterprise office and many other organizations. By default MikroTik Hotspot uses HTTP CHAP login method where user must provide username and password to get internet service. Sometimes we may face that some users are not eager to provide username and password to get internet service or we cannot ask some users to put username and password to get internet due to [...]
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MikroTik Port Forwarding using Winbox | July 23, 2018
MikroTik Port Forwarding or Port Mapping is a NAT application that is used to redirect a request from MikroTik IP address and port number combination to a local IP address and port number. For example, if you have a Web Server or FTP Server in your private/local area and want to access this local server from outside of your local area (from internet/public), you can apply MikroTik port forwarding or port mapping and can easily access your Web Server or [...]
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How to Install Extra Packages in MikroTik RouterOS | October 10, 2019
MikroTik RouterOS does not always include all the packages those are developed by MikroTik team. So, sometimes you may find that some packages are missing in your RouterOS such as NTP package, DUDE package, Wireless package, CAPsMAN package and so on. Specially, user manager package which is totally a separate MikroTik RADIUS package used to manage user authentication, authorization and accounting is always missing. Also upgrading RouterOS or downgrading RouterOS you may find that some packages are missing there. So, [...]
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Network Bandwidth and Throughput | February 17, 2017
Bandwidth and Throughput are two important basic networking terms in computer network. If you wish to be an expert network administrator, you must have better understanding about these two networking terms. As a network user, you should also have better understanding about network bandwidth and throughput so that you can get maximum output from your network service provider. In this article, I will explain about network bandwidth and throughput from very beginning. I hope, this article will enrich your networking [...]
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Free Internet Speed Test Online | August 31, 2015
You are here because you want to check your broadband internet speed. Don’t worry, I will show you how to check your internet speed from online absolutely free and fastest way. I will show you top 4 websites link from which your broadband internet speed can be checked so easily. I will also show you how to check bandwidth usage continuously with windows operating system’s utility and a third party software utility. So, keep reading this article and find how [...]
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How to Block Free Proxy Access with MikroTik Router | May 21, 2019
Proxy Server is an alternative to VPN that breaks blocking firewall of a network. If any user uses free web proxy server with web browser, the web request is processed by the proxy server. So, blocking firewall rule is not applied on the proxy enabled PC. For this, system administrators should be careful enough to block free proxy servers along with blocking VPN access. In my previous article, I discussed how to block VPN access with MikroTik Firewall. In this [...]
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MikroTik Hotspot Login Page with Random MAC Detection | October 5, 2025
Hotspot businesses such as cafés, restaurants, co-working spaces, schools, and ISPs often rely on MikroTik Hotspot solutions to provide Wi-Fi access. One common challenge is that many modern devices (Android, iOS, Windows, macOS) use randomized (private) MAC addresses, which can cause repeated logins, loss of session persistence, and difficulties with usage tracking. To solve this problem, we have designed a professional Hotspot Login Page Template that not only looks modern and mobile-friendly but also detects randomized MAC addresses and notifies [...]
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CentOS 7.5 Installation with GUI and LVM Partition | March 7, 2019
Red Hat/CentOS Linux is a popular server operating system. Specially who work on mail server, web server, web proxy server, ftp server and file server are so familiar with the Red Hat/CentOS Linux. In my previous article, I discussed how to install CentOS 7.5 Linux step by step with the standard partition. But if you want to work on mail server, web proxy server, ftp server, file server or any other application where disk space changes frequently, the standard partitioning [...]
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MikroTik Hotspot with Bandwidth Limitation and Prepaid Billing System | January 14, 2018
Say, you are a network administrator and want to establish a network that will have user bandwidth package management facility with prepaid billing system as well as partner advertisement facility. Then, MikroTik Hotspot Server Configuration with MikroTik User Manager Radius Server will be a wise decision. Because, MikroTik User Manager Radius Server is a user authentication, authorization and accounting application that will give facility to manage user bandwidth package with prepaid billing system. On the other hand, you can easily [...]
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