Author: Rahul

I, Rahul Kumar am the founder and chief editor of TecAdmin.net. I am a Red Hat Certified Engineer (RHCE) and working as an IT professional since 2009..

RPM Stands for Redhat Package Manager. RPM command is used for managing rpm software packages in your linux machine. Using rpm command we can install, upgrade, remove, list packages. 1. Installing RPM in System. Use below command to install and vsftpd RPM in system. # rpm -ivh vsftpd-2.3.5-2.el6.i686.rpm Sample output: warning: vsftpd-2.3.5-2.el6.i686.rpm: Header V3 DSA/SHA1 Signature, key ID e9bc4ae1: NOKEY Preparing… ########################################### [100%] 1:vsftpd ########################################### [100%] 2. Update the installed RPM Package. If you already installed an RPM so you can simply upgrade it with new version. # rpm -Uvh vsftpd-2.3.5-2.el6.i686.rpm 3. Check installed RPM Package. After installation of a…

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I had created this rpm few months back. Now it is available for all users. This rpm have a simple shell script for mysql database backup. Features: Takes database backup locally. Upload backups to ftp server. Send email alerts on backup completed. Installation: Download this rpm directly using command line or using given below download link and install it. [wpdm_file id=4] # wget https://tecadmin.net/wp-content/downloads/rpms/mydumpadmin-1-0.noarch.rpm # rpm -ivh mydumpadmin-1-0.noarch.rpm Preparing… ########################################### [100%] 1:mydumpadmin ########################################### [100%] Thank you for installing this RPM. Configure backup settings in /etc/mydumpadmin/settings.conf file Setup /etc/mydumpadmin/mysql-dump.sh script in your cron to take backup automatically 0 2 * *…

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GPG basic file encryption doesn’t required public/private key. But to make a encrypted file more secure you can use RSA/DSA algorithms. These algorithms generates public and private keys to encrypt file. This article will help you to do following three tasks for File Encryption using GPG Key Pair in Linux. Create key pair Encrypt/Decrypt file locally for same user account. Encrypt file for other user. Decrypt other users file. Step 1: Create GPG Key Pair The very first step is to generate key pair. Use the following command to generate gpg key pair. # gpg –gen-key Output: gpg (GnuPG) 1.4.5;…

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GNU TAR (Tape ARchive) combines multiple files together into a single tape or disk archive, and can restore individual files from the archive. Here are some Linux tar command with Useful practical examples. Some useful command line switches are given below, which are used in this article. -c => create a new archive file -v => show the detailed output (or progress) of command -x => extract an archive file -f => specify file name of an archive -z => Use archive through gzip -j => Use archive through bzip2 -J => Use archive through xz -t => viewing content…

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The zip command is used for compression and file packaging under Linux/Unix operating systems. unzip is used for decompress an archive. See the below examples of some typical uses of zip and unzip. 1. Zip all files in a directory This command will create zip of all files in /backup directory. I will not archive files under the sub directories recursively. zip backup.zip /backup/* Sample Output: adding: backup/anaconda.ifcfg.log (deflated 47%) adding: backup/anaconda.log (deflated 78%) adding: backup/anaconda.program.log (deflated 84%) adding: backup/anaconda.storage.log (deflated 90%) adding: backup/boot.log (deflated 72%) adding: backup/dracut.log (deflated 92%) adding: backup/httpd/ (stored 0%) adding: backup/kadmind.log (deflated 74%) adding: backup/krb5kdc.log…

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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…

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PostgreSQL is a open source object-relational, highly scalable, SQL compliant database management system. This article will help you for installing PostgreSQL 9.1 on CentOS 5/6 and RHEL 5/6. Step 1: Add PostgreSQL Yum Repository First step is to install postgres repository in your system, Use one of below commands as per your system architecture and operating system. CentOS/RHEL 5, 32-Bit: # rpm -Uvh http://yum.postgresql.org/9.1/redhat/rhel-5-i386/pgdg-centos91-9.1-4.noarch.rpm CentOS/RHEL 6, 32-Bit: # rpm -Uvh http://yum.postgresql.org/9.1/redhat/rhel-6-i386/pgdg-centos91-9.1-4.noarch.rpm CentOS/RHEL 5, 64-Bit: # rpm -Uvh http://yum.postgresql.org/9.1/redhat/rhel-5.0-x86_64//pgdg-centos91-9.1-4.noarch.rpm CentOS/RHEL 6, 64-Bit: # rpm -Uvh http://yum.postgresql.org/9.1/redhat/rhel-6.3-x86_64/pgdg-centos91-9.1-4.noarch.rpm Step 2: Install PostgreSQL Server 9.1 using Yum. Below command will install PostgreSQL 9.1 on…

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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…

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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…

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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…

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