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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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CentOS 7 Partition Management with fdisk Utility | February 11, 2019
CentOS or Red Hat Linux is a popular server operating system to the system administrators. Almost all the system admins or IT guys who play with mail server, file server, proxy server and so on are so known with CentOS or Red Hat Linux and cannot go a single day without this operating system. The guys who are also wish to be a system admin should be familiar with CentOS or Red Hat operating system. In my previous article, I [...]
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MikroTik CAPsMAN and CAP Basic Configuration using Winbox | February 20, 2020
MikroTik CAPsMAN (Controlled Access Point system Manager) is a centralized Access Point management application provided by MikroTik. MikroTik introduces CAPsMAN from RouterOS v6.11 with CAPsMAN v1 and from RouterOS v6.22rc7 CAPsMAN v2 is running. If you have multiple MikroTik CAPs (Controlled Access Point) in your organization, CAPsMAN provides an easy way to maintain client data as well as CAPs configuration centrally. In my previous article, I discussed how to configure MikroTik Wireless Router as an Access Point. In this article, [...]
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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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MikroTik Hotspot Login by HTTP CHAP, HTTP PAP and HTTPS | July 25, 2020
MikroTik Hotspot uses various types of login methods. Among these login methods HTTP CHAP, HTTP PAP and HTTPS are basic and important login methods. So, a MikroTik system administrator should have proper understanding on Hotspot HTTP CHAP, HTTP PAP and HTTPS login methods. In my previous article I discussed how to configure MikroTik Hotspot using Winbox. In this article I will discuss how to use HTTP CHAP, HTTP PAP and HTTPS login methods properly in MikroTik Hotspot Server. MikroTik Hotspot [...]
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MikroTik Site to Site VPN Configuration with IPsec | March 8, 2018
VPN (Virtual Private Network) is a technology that provides a secure and encrypted tunnel across a public network. A private network user can send and receive data to any remote private network using this VPN Tunnel as if his/her network device was directly connected to that private network. Site to Site VPN technique establishes a secure tunnel between two routers across public network and local networks of these routers can send and receive data through this VPN tunnel. MikroTik RouterOS [...]
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MikroTik L2TP/IPsec VPN Configuration (Connecting Remote Client) | February 26, 2018
VPN (Virtual Private Network) is a technology that provides a secure and encrypted tunnel across a public network and using this VPN tunnel a private network user can send and receive data to any remote private network as if his/her network device was directly connected to that private network. MikroTik L2TP server is one of the most popular VPN services. It provides a secure and encrypted tunnel across public network for transporting IP traffic using PPP. L2TP/IPsec is more secure [...]
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How to Block VPN Access with MikroTik Router | May 14, 2019
Sometimes system administrators create firewall rule to block unwanted websites. But VPN apps break these firewall rules and allow access to unwanted websites. For example, if Facebook is blocked with MikroTik Firewall and any expert user installs and enables VPN apps (such as OpenVPN, Hotspot Shield, ProtonVPN, NordVPN, PureVPN etc.), he can easily get access to Facebook. So, system administrators should also block popular VPN apps so that user cannot use those VPN servers. Blocking VPN apps is not so [...]
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MikroTik Router Static DHCP Server Configuration | October 25, 2015
DHCP Server assigns IP address and other related IP information (Subnet mask, Gateway and DNS) automatically to network devices. But automatic DHCP Server has some disadvantages too. If any IP device connects to any automatic DHCP network, the device will get an IP address and related IP information automatically by the DHCP Server and the device will start to use resources of this network. In this situation, the network administrator cannot know who is being connected to the network and [...]
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MikroTik Load Balancing over Multiple Gateways (2 WAN) | October 13, 2016
Load Balancing is a technique used to send network traffic over multiple gateways. If you have multiple ISP connections in your network, you can send your network traffic through those ISP connections and can make a load balancing network. Accidently you may ask me, why will I use multiple ISP connections? What are the benefits to use multiple ISP connections in my network? I will say, ask yourself deeply then you will find the reasons why multiple ISP connections is [...]
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