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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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Hardening MikroTik RouterOS by Limiting Login Services | February 6, 2021
MikroTik RouterOS is usually used as a bridge between WAN and LAN network. WAN network is always an insecure network because attackers always try to hack your RouterOS so that they can compromise it for their own benefit. As a network administrator of MikroTik RouterOS, we should always take anti hacking steps to secure our MikroTik RouterOS. There are a lot of security tasks those we should take care to secure our MikroTik RouterOS. Among these security tasks, we will [...]
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Apache2 Web Server HTTPS Configuration on Ubuntu Server | August 15, 2021
Data transmission between web server and web client over port 80 (HTTP) is not encrypted. So, any middle man between web server and web client can view transmitted data and can steal secret information. To overcome this limitation, HTTPS Protocol over port 443 has been introduced. HTTPS is a secure web server that is configured with SSL/TLS certificate. TLS (Transport Layer Security) and its predecessor SSL (Secure Sockets Layer) are web protocols used to wrap normal traffic in a protected, [...]
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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 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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Computer Network Topology Outline | September 12, 2017
The first thing that has to study about a network is its physical shape or design layout. It will be extremely important when a wiring scheme and design are selected for a new network installation. Actually Network Topology refers to physical shape or design layout of a network. Network topology determines how different nodes in a network are connected and how these nodes communicate to each other. Types of Computer Network Topology Network really has two shapes or two types [...]
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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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VMware ESXi 6.7 Installation and Basic Configuration | November 17, 2020
VMware vSphere is the pioneer in virtualization. No other virtualization software is as feature rich as VMware vSphere. More than 500,000 enterprise data center are now using VMware vSphere. It is expected that most of the data center will be turned into virtualization near future. As VMware vSphere provides more feature than any other virtualization software, it is also expected that demand of VMware vSphere will be increased day by day. VMware ESXi is the foundation of VMware vSphere and [...]
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MikroTik Dual WAN PCC Load Balancing with PPPoE Server | July 5, 2018
Hi geek, you are here because you are finding a complete MikroTik Dual WAN PCC Load balancing and Link Redundancy solution with PPPoE Server because you have managed two ISP connections and want to provide an uninterrupted internet connection to your clients. You also want to manage your LAN clients with PPPoE Server because it provides a hassle free network administration. MikroTik PCC provides 100% reliable Load Balancing and Link Redundancy network and in my previous article I discussed how [...]
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FreeRADIUS MySQL Database GUI with phpMyAdmin on CentOS 7 | January 30, 2019
FreeRADIUS is a high performance RADIUS Server that accepts a large number of networking devices as RADIUS Client including MikroTik Router. MySQL is one of the best user sources for freeRADIUS server. In my previous article, I discussed how to install freeRADIUS server on CentOS 7 and how to integrate MySQL module with freeRADIUS server. I also discussed how to create user group and profile in MySQL database server and authenticate MikroTik PPPoE client with MySQL database user. I used [...]
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