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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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Troubleshooting Common Issues with Security Cameras in MikroTik Networks | February 7, 2025
30 Seconds Summary When fixing security cameras on MikroTik networks, you might see issues like bad video quality, connections dropping, motion detection not working, and security weaknesses. These problems can happen because of not enough internet speed, network congestion, IP conflicts, old software, or weak security. To fix these, make sure you have enough internet speed, set up the IP settings correctly, give camera traffic priority, and update the software regularly. Also, protect the cameras with strong passwords and encryption. [...]
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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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How to Block Tor Browser with MikroTik Router | June 12, 2019
Tor Browser is an alternative to VPN and Web Proxy that breaks blocking firewall rule. If any user installs and uses Tor Browser, he/she can hide the public IP address of router and can unblock blocked websites applied on a network. So, administrators should block Tor Nodes along with other blocking firewall rule. In my previous article, I discussed how to block VPN and Proxy access with MikroTik Router and in this article I will discuss how to block Tor [...]
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MikroTik Site to Site EoIP Tunnel with IPsec | March 21, 2018
VPN (Virtual Private Network) is a technology that provides a secure tunnel across a public network. A private network user can send and receive data to any remote private network using VPN Tunnel as if his/her network device was directly connected to that private network. MikroTik provides EoIP (Ethernet over IP) tunnel that is used to create a site to site VPN. EoIP tunneling is a MikroTik RouterOS protocol that creates an Ethernet tunnel between two MikroTik Routers on top [...]
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MikroTik Configuration with PPPoE WAN Connection | July 18, 2018
MikroTik Router is a popular routing device to any network administrator because of having a lot of network features availability. MikroTik PPPoE Client is a special feature that is used to connect any PPPoE Server. If your ISP provides PPPoE connection, MikroTik Router is able to connect that PPPoE Server using PPPoE Client. In my previous article, I discussed how to configure MikroTik Router with static WAN connection and in this article I will show how to configure MikroTik Router [...]
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Static Routing Configuration in MikroTik Router | February 11, 2018
Static Routing is an important topic to any network administrator who works with multiple MikroTik RouterOS and wants to establish communication among Router’s local networks. For example, say a network administrator maintains two MikroTik RouterOS connected with any communication medium and each RouterOS has its own networks and network resources such as servers, printers etc. and he wants that each network and network resources will be accessible from other networks. In this case, static routing configuration between two RouterOS will [...]
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How to Block MAC Address in MikroTik RouterOS 7 | July 11, 2024
MikroTik RouterOS 7 by default allows any MAC address to get internet connection through it. But we may need to block some MAC addresses sometimes. There are three methods to block MAC address in MikroTik RouterOS 7 – Blocking MAC Address using Bridge Filter Rule. Blocking MAC Address using Firewall Filter Rule and Blocking MAC Address from DHCP Lease. We can use any of these methods if we want to block MAC Address in MikroTik Router. In this article, we [...]
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Red Hat/CentOS 7 Linux Installation (Minimal Packages) | April 18, 2017
Linux is a free and open source operating system developed by Linus Torvalds on September 17, 1991. It is mainly used as server environment. A lot of Linux distributions are present today. Among them, Red Hat Linux is used as enterprise Linux. Red Hat is also known as Red Hat commercial Linux that means Red Hat is a paid service program. CentOS (Community Enterprise Operating System) is another Linux distribution that provides a free and open source, enterprise-class, community-supported server platform functionally [...]
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MikroTik PPPoE Setup with Radius Server Prepaid Billing System | December 23, 2017
MikroTik PPPoE Server is popularly used in ISP Companies to maintain user connection. Along with MikroTik PPPoE Service it is a better idea to make a prepaid billing system with Radius Server. MikroTik User Manager Radius Server is a user authentication and accounting application that gives the ISP Company ability to manage PPPoE user’s connection with proper bandwidth management as well as their prepaid billing system with scratch card. So, any ISP Company can turn a smart network system with [...]
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