Author: Rahul

The zip command in Linux is a utility used for packaging a group of files into a zip archive. The zip command can also be used to compress files, making them take up less space on your computer’s hard drive. In addition, the zip command can be used to encrypt files, making it more difficult for unauthorized users to access the contents of the zip archive. To unzip a zip archive, you can use the unzip command. This command will decompress the files in the zip archive, allowing you to access them. Zip Command Examples Go through the below real…

AS we know, now a days it’s not safe to send and receive data over internet. There are many option available to secure your data while traveling over internet. GnuPG also provides you to encrypt your data on key basis and transfer them securely over internet. GPG is an encryption and signing tool for UNIX/LINUX like OS. GnuPG provides many methods for file encryption and decryption. click here to read more about GnuPG. This article will help you about File Encryption using GPG key on linux system. Step 1: Create Test File Firstly create a test file to encrypt. you…

RNDC controls the operation of a name server. rndc uses tcp connection to communicate with bind server for sending commands authenticated with digital signatures. Configure RNDC Key for Bind9 using below steps. Step 1: Create RNDC Key and Configuration File First step is to create rndc key file and configuration file. rndc provides command line tool rndc-confgen to generate it. # rndc-confgen Sample Output: # Start of rndc.conf key “rndc-key” { algorithm hmac-md5; secret “DTngw5O8I5Axx631GjQ9pA==”; }; options { default-key “rndc-key”; default-server 127.0.0.1; default-port 953; }; # End of rndc.conf # Use with the following in named.conf, adjusting the allow list…

Command named-checkconf checks the syntax only of a DNS (bind) configuration file. The file is parsed and checked for syntax errors, along with all files included by it. If there is no file specified with the command, /etc/named.conf is read by default. 1. Check bind9 (DNS) Configuration In case of any changes done in the bind configuration, I recommend checking the DNS configuration file before restarting the service. named-checkconf /etc/named.conf If the bind is running in chroot environment use the below command also along with the above command named-checkconf -t /var/named/chroot /etc/named.conf The above command will show nothing if there…

The DNS (Domain Name System) is a distributed system, used for translate domain names to IP address and vice a versa.For example when we type domain name in browser url like “https://tecadmin.net”, Our computer sends a request to DNS and get an ip address of domain. This article will help you to step by step setup dns server on CentOS and RedHat systems. Network Scenario: DNS Server IP: 192.168.1.254 DNS Server Name: ns1.tecadmin.net, ns2.tecadmin.net Domain Name: demotecadmin.net Domain IP to point: 192.168.1.100 Step 1 – Install Bind Packages Bind packages are available under default yum repositories. To install packages simple…

xargs is a Linux/Unix powerful command to build and execute command lines from standard input. It takes output of a command and pass it as argument of another command. xargs takes standard input, delimited by blanks or newlines, and executes the command one or more times with any arguments followed by items. Blank lines on the standard input are ignored. Syntax xargs [OPTION]… COMMAND [INITIAL-ARGS]… Here the COMMAND is executed with arguments INITIAL-ARGS and more arguments read from the input. xargs Command Options The xargs commands provides a limited number of command line arguments but enough to utilize its features.…

Fsniper is a useful tool for directory monitor, and execute predefined actions on files created or modified in that directory. For example, if we want to make a backup of each files created in your web upload folder or ftp directory, Using fsniper we can copy all files created in that folder to backup disk. Fsniper uses inotify to watch for when a file is closed after being written to. Step 1: Install Required Packages First install the required packages for fsniper installation on your system. # yum install file-libs file-devel pcre pcre-devel Step 2: Download Fsniper Source Download the…

wget is Linux command line utility. wget is widely used for downloading files from Linux command line. There are many options available to download a file from remote server. wget works same as open url in browser window. Tip 1: Download File using Wget Below example will download file from server to current local directory. $ wget https://tecadmin.net/file.zip Tip 2: Download File & Save to Specific Location Below command will download zip file in /opt folder with name file.zip. -O is used for specify destination folder # wget https://tecadmin.net/file.zip -O /opt/file.zip Tip 3: Download File from FTP Some time you…

What is Checken/Egg Problem. Chicken/Egg problem occurred in booting process of Linux. A Linux kernel required modules to mount root partition which typically uses ext3 file system, LVM, RAID, etc. All the Linux modules resides in /var/lib/($uname -r) directory but Linux kernel could not access them without mounting it. So the problem was that how Linux kernel access modules required to mount root partition. How Linux Kernel Get it Solve The grub boot loader and Linux kernel works together to get solve this problem using Initial Ram Disk ( initrd ), which is part of GRUB specification for a Linux…

Optimize your Java development and runtime environment with this comprehensive guide on installing Java Development Kit (JDK) and Java Runtime Environment (JRE) on Linux systems. Java developers need both JDK and JRE to craft and run Java applications and applets efficiently. JDK offers the essential tools for developing Java applications, including the Java compiler, while JRE provides a runtime environment necessary for Java applications. How to Install Java on Ubuntu and Linux Mint This guide simplifies the process of installing OpenJDK Java on popular Linux distributions such as Ubuntu and Linux Mint. OpenJDK, an open-source implementation of the Java Platform,…