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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 UserMan RADIUS Server Customers, Users and Routers |   November 13, 2017

    MikroTik User Manager RADIUS Server is a centralized user authentication and accounting application that gives the ISP Company or network administrator ability to manage MikroTik RouterOS user, PPP user and Hotspot user so smoothly. There are two methods to install MikroTik User Manager RADIUS Server in your network. You can install User Manager Package either on a physical RouterOS or on a dedicated Server Machine or on a Personal Computer where RouterOS is running. How to install and configure User [...]

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    MikroTik RouterOS User Authentication via RADIUS Server |   November 19, 2017

    MikroTik RouterOS has a strong local user database that is enough to manage a single MikroTik RouterOS user. But if your network has more than one MikroTik Routers, it is always better to use a RADIUS server to manage RouterOS user centrally. MikroTik User Manager RADIUS Server is a centralized user authentication and accounting application that gives the ISP Company or network administrator ability to manage not only RouterOS users but also PPP, Hotspot, DHCP and Wireless users. How to [...]

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    6 Best VPN Providers to Consider in 2022 |   October 19, 2021

    There are many VPN providers on the market. It can be difficult to know which one is best for you, but luckily we have compiled a list of six of the best! Get ready for our top picks. What is a VPN? A VPN, or virtual private network, hides and encodes your internet traffic so that you can surf the web more securely. By doing so, it protects your data from hackers and prying eyes. Think of a VPN as [...]

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    Red Hat/CentOS Network Configuration |   August 4, 2017

    Red Hat/CentOS network configuration or IP configuration is an important task to a Linux system administrator. After completing RedHat 7/ CentOS 7 fresh installation, you have to first configure your system network so that it can communicate to other network devices. In my previous article, I discussed how to install CentOS 7 core packages successfully on your physical machine. If you are a new CentOS 7 user and yet you have not installed CentOS on your machine, feel free to study [...]

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    Virtual Web Hosting with Apache on CentOS 7 (Name Based) |   July 15, 2019

    Virtual Hosting is a method of hosting multiple domains on single server. If you have multiple domains (such as domain1.com, domain2.com and so on) and want to host on a webserver, Virtual Web Hosting is your right choice. Apache web server provides an easy way to manage Virtual Hosting. Virtual Hosting can be either Name Based or IP Based. In Name Based Virtual Hosting, multiple domains can be hosted on single IP address. On the other hand, in IP Based [...]

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    MikroTik Site to Site OpenVPN Server Setup (RouterOS Client) |   April 9, 2018

    VPN (Virtual Private Network) technology provides a secure and encrypted tunnel across a public network. So, a private network user can send and receive data to any remote private network through VPN tunnel as if his/her network device was directly connected to that private network. MikroTik OpenVPN Server provides a secure and encrypted tunnel across public network for transporting IP traffic using PPP. OpenVPN Server uses SSL Certificates. So, OpenVPN Tunnel is a trusted tunnel to send and receive data [...]

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    How to Block WiFi Access although Password is Known |   April 23, 2024

    We usually get internet connection from any ISP and buy any WiFi Router and then configure wireless/AP with password and configure DHCP Server to get connection from own WiFi devices. We use these WiFi Routers/APs at home, office, workspace or any other public places. Usually, we get connected to our WiFi using our provided WiFi password. Initially there will be no problem to keep your network safe using password authentication. But day by day your password will be known by [...]

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    OpenVPN Configuration over Port 443 on Ubuntu Linux |   June 20, 2022

    OpenVPN provides a secure and encrypted VPN tunnel across public network. Unlike PPTP and L2TP VPN Services which can be blocked, OpenVPN can highly be customized and even can be run over 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 Server can easily install on Ubuntu Server. Installing OpenVPN Server on Ubuntu Server, we can connect Windows, [...]

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    User Management in Linux (Red Hat/CentOS) |   September 28, 2017

    User management is an important part of Linux (especially Red Hat Enterprise Linux) system administration. Linux users can be administrated using user or group administration GUI (Graphical User Interface) tool as well as through Red Hat/CentOS Linux command prompt. But I will always suggest you to do command line user administration as much as possible because in production GUI will not be provided always. Many people who are learning Linux administration do not know all features of user administration command [...]

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