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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 WebProxy Log Analyzer Configuration | August 30, 2016
MikroTik RouterOS generally logs various system events and status information. Logs are mainly saved in router’s memory (RAM) or disk. MikroTik logs can also be sent by email or even can be sent to a remote syslog server. All logs those are saved in router’s local memory can be viewed from Log menu. Any log entry that is saved in local memory contains time and date when event occurred, topics that this message belongs to and message itself. But local [...]
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CentOS 8 Networking Configuration Using Cockpit Web Console | January 11, 2021
The first task after completing CentOS 8 fresh installation is to configure its networking so that it can be accessed from other network devices. In my previous article, I discussed how to install CentOS 8 Graphical User Interface (GNOME Desktop) with step by step screenshots. If you are a new CentOS 8 user and have not yet installed CentOS 8 on your server machine, feel free to follow that article and install CentOS 8 GNOME Desktop according to the article. [...]
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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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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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FreeRADIUS User Profile Configuration for MikroTik Router | January 10, 2019
FreeRADIUS is a high performance RADIUS application that accepts a large number of network devices as RADIUS Client including MikroTik Router. FreeRADIUS MySQL module helps to get user authentication and authorization information from database server and to store user accounting information in database server. Configuring MySQL user group and profile properly, freeRADIUS user restriction can easily be maintained. How to configure user group to apply user limitation was discussed in my previous article. In this article, I will discuss how [...]
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Restrict Internet Access Based on MAC Address in MikroTik | February 4, 2017
MikroTik router has a lot of features by which a network administrator can design his network as he likes. As a network administrator, sometimes you may need to allow internet access some specific devices. If other devices try to access internet, they will be rejected by your router. For example, say, you have configured a simple network like below diagram. In this network, you have configured WAN, LAN, Gateway, DNS and NAT. Also you have created queue rules for limiting [...]
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MikroTik Radius Configuration with FreeRADIUS and MySQL | December 18, 2018
FreeRADIUS is a modular RADIUS suite. A lot of modules such as Perl, python, MySQL etc. can be integrated with freeRADIUS to enrich freeRADIUS features. MySQL is one of the best user and client sources in freeRADIUS server. One of the important advantages of MySQL with freeRADIUS server is that MySQL can easily be controlled with a lot of programming languages including PHP. So, freeRADIUS users and their authentication, authorization and accounting can easily be controlled graphically using MySQL database [...]
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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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Setting Google as Default Search Engine | September 30, 2015
Google is one of the most popular search engines to any online user. It is said that no online user cannot go a single day without Google search engine. Google search statistics shows that over 40,000 search queries are processed every second by Google. If you have any query about any subject, just type in Google search box and Google will show you billion of results related to your search query within less than a second. So, usually you will want [...]
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