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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 Multiple SSID with Separate LAN and DHCP Server | October 30, 2019
One of the most amazing features of MikroTik Wireless Router is creating Multiple SSID (Virtual AP) on a physical wireless interface. So, creating a Guest WiFi AP with separate LAN block, SSID and DHCP Server is so easy using MikroTik WiFi AP Router. In the previous article, I discussed how to configure MikroTik WiFi Access Point on physical wireless interface with DHCP Server using hAP Lite (RB941-2nD) Wireless Router. In this article I will discuss how to configure a Virtual [...]
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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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MikroTik OpenVPN Configuration on TCP Port 443 with Windows OS | April 6, 2020
MikroTik OpenVPN is an amazing VPN solution. IT provides a secure and encrypted VPN tunnel across public network. Unlike PPTP and L2TP VPN Services which are poorly designed and can easily be blocked, OpenVPN can highly be customized and even can be run on so popular TCP Port 443. So, OpenVPN cannot easily be blocked. OpenVPN uses SSL/TLS Certificates. So, OpenVPN Tunnel is a trusted tunnel to send and receive data across public network. OpenVPN is a site to site [...]
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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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PPPoE Server Configuration in MikroTik RouterOS 7 | December 2, 2023
MikroTik PPPoE is a client-server protocol and mostly used at the end ISP configuration where MikroTik RouterOS acts as a PPPoE Server and user’s WiFi Router acts as PPPoE client. MikroTik PPPoE Server can be used with MikroTik simple queue management. So, it helps to manage user’s bandwidth easily. People who are trying to do internet business should learn MikroTik PPPoE Server. Configuring PPPoE Server in MikroTik RouterOS 7 is so easy. If you have knowledge on basic RouterOS 7 [...]
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Enable F8 Menu to Enter Safe Mode in Windows 8 & 10 | August 27, 2015
Windows is the most popular operating system in the world. No computer user can go a single day without windows operating system. As windows is a popular operating system, it has a lot of viruses also. But windows provides various tools for removing these viruses. For removing any unwanted program, windows safe mode is a best option. A popular way to open windows safe mode is windows Advanced Boot Options. Advanced Boot Options provides different run levels for windows users so [...]
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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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How to Block a Phone from WiFi Router | May 8, 2024
We usually buy a WiFi Router from market and configure SSID and password to access it. We also configure DHCP Server so that whenever a phone or IP device gets connected to this SSID with the password, the device can get an IP address automatically and can get internet access. It is not possible to secure the WiFi Network keeping only the password authentication method. Because the password can be shared by the users or can be hacked easily. So, [...]
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How to Backup and Restore Mozilla Firefox Bookmarks | August 13, 2015
Bookmark is one of the most important and useful features in Mozilla Firefox Browser. If Bookmark is lost, Firefox users become very anxiety to recover it. But Mozilla Firefox also provides a tool to backup and restore Bookmarks so easily. So don’t need to be worried. If you know the proper steps about how to take a backup of your bookmark file and how to restore that bookmark backup file again, it will be very beneficial for you. So, this [...]
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