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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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DHCP Server Configuration in MikroTik RouterOS 7 | October 14, 2015
Dynamic Host Configuration Protocol (DHCP) is a client/server protocol. DHCP server automatically provides an Internet Protocol (IP) address and other related information such as subnet mask, default gateway and DNS to DHCP clients. DHCP server and client use UDP port 67 and 68 for communication. In a network, a DHCP client (IP devices such as Desktop, Laptop, Smartphone etc.) requests for an IP lease to DHCP servers and a DHCP server responses allocating IP address and other related IP information [...]
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Install MikroTik RouterOS on PC | June 13, 2016
MikroTik is a popular and mostly used router worldwide because of having a lot of networking functionalities and its cheap price. If we buy a MikroTik Routerboard (like MikroTik Routerboard 450G, MikroTik Routerboard 1100 AH etc.), we will find a machine where MikroTik RouterOS is prebuilt but the machine contains limited processing resources such as limited RAM and limited processor core. So, our network could be slow if you use a MikroTik RouterBoard for maintaining a large network. On the [...]
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OpenVPN Client Configuration in Windows 10/11 | June 29, 2022
OpenVPN is an excellent VPN solution for transmitting data securely over public network. Configuring an OpenVPN Server either on MikroTik RouterOS or Ubuntu Server, we can access local servers or devices from remote place using Windows 10/11, Android or MacOS. How to configure OpenVPN Server in Ubuntu Server was discussed in the previous article. In that article, I also discussed how to create a new OpenVPN client (for Windows OS) who will be able to connect the OpenVPN Server. So, [...]
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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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Securing MikroTik Router with Port Knocking | March 21, 2021
MikroTik Port Knocking strategy helps to protect MikroTik Router from hackers and unauthorized access as well as enhances MikroTik RouterOS security.
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MikroTik Blocking Websites with TLS Host Firewall Matcher | April 29, 2019
Most of the websites now use https and blocking https websites is so much harder with the MikroTik RouterOS version less than 6.41. But from RouterOS v6.41, MikroTik Firewall introduces a new property named TLS Host that is capable to match https websites so easily. So, blocking https websites like Facebook, YouTube etc. can be easily done with MikroTik Router if RouterOS version is greater than 6.41. In my previous article, I discussed how to block websites with MikroTik Router [...]
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Free Online File Storage and File Sharing with Google Drive | August 19, 2015
Google Drive is a popular free online file storage and file sharing service by Google. Google Drive provides 15 GB free online storage where anyone can store or backup any kinds of file. That means, you can store your document file, picture, audio, video or any kinds of file into Google Drive and can read, write or download any file when you want. You can also share your stored file with your friends using Google Drive. But you are only [...]
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MikroTik Site to Site GRE Tunnel Configuration with IPsec | March 26, 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 GRE (Generic Routing Encapsulation) tunnel that is used to create a site to site VPN tunnel. GRE tunneling protocol which can encapsulate a wide variety of protocols creating a virtual point-to-point link was [...]
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MikroTik PCC Load Balancing over Unequal Dual WAN Links | June 12, 2018
Hi, you are here means you are finding a Load Balancing and Link Redundancy solution with Unequal WAN links in your MikroTik Router. If so, it is your right place. In my previous article I discussed how to configure a Dual WAN Load Balancing and Link Redundancy network using PCC method but it was assumed that both WAN links have equal bandwidth. But in real situation, you may have unequal WAN links such as ISP1 may have 10MB bandwidth and [...]
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