Monday 19 November 2018

How to change password for a MySQL user



Follow the below MySQL commands to reset the password for a MySQL user. You can change the password for any other users as well with the below commands.

Sunday 18 November 2018

How to configure apache mod_status module in CentOS 7



Apache module mod_status is an open source module that allow to monitoring web server load, statistics, current state including worker processes and active connections.

How to Block a specific IP Address using Routing Table in CentOS 7



The Linux routing table can block the incoming connection to prevent the Denial of Service (DoS) and save resource utilization. The Linux routing tables can used to block such IP addresses or whole subnet with reject route and null route.

Thursday 15 November 2018

How to Zip and unZip Files to a specific directory in CentOS 7



Zip is a simple and commonly used utility for compression and decompression folders that can compress from level 1 to 9.

How to create Database Dump with routine, triggers and procedures using MySQLDump



Mostly, MySQLDump is used for taking backup of MySQL data backups. MySQL provide a mysqldump scripts with the multiple options to take dump of MySQL Databases. MySQLDump will take backup by default of all the triggers but not the stored procedures and functions.

How to create Database Dump using MySQLDump



Mostly, MySQLDump is used for taking backup of MySQL data backups. MySQL provide a mysqldump scripts with the multiple options to take dump of MySQL Databases.

Sunday 11 November 2018

How to copy data from AWS instance using Rsync in Centos 7



Rsync is open source software that used to synchronize files/folders from local to local computers and remote computers as well over SSH with compression and encrypted files.

Saturday 10 November 2018

How to enable SCL Repository in Cent OS 7



The Software Collections (SCL) repository is created to provide safely installation on Cent OS and RHEL and also provide installation of multiple software versions on the same machine. The SCL is available yum default repository on Cent OS 6.5 and later.

Thursday 8 November 2018

How to Change Default MTA in CentOS 7




If there is two or more programs (sendmail, postfix, SSMTP and exim etc) are installed for MTA and required to change default MTA. CentOS 7 provide alternatives command to select a default MTA.

Change Default MTA: Run the below command and follow instructions to change default MTA:

[root@linuxcnf ~]# alternatives --config mta

There is 1 program that provides 'mta'.

  Selection    Command
-----------------------------------------------
*+ 1           /usr/sbin/sendmail.postfix
   2           /usr/sbin/sendmail.ssmtp

Enter to keep the current selection[+], or type selection number: 2
[root@linuxcnf ~]#

There are 2 programs which provide 'MTA'. Enter number 2 and press enter for ssmtp selection as a default MTA. Also stop the postfix service and disable to start on boot up.

Wednesday 7 November 2018

How to Install and Configure SSMTP in CentOS 7




SSMTP is a very simple and useful alternative of send mail and postfix. It provides the functionality to send mails via the standard user/agents and authentication with valid mail account to send mails. It is used to send mails on local and external domains.
SSMTP is available in EPEL repository (Extra Packages for Enterprise Linux) for CentOS 7.

Tuesday 6 November 2018

How to Encrypt/Decrypt Files in CentOS7/RHEL7 using Ccrypt



Ccrypt is a command line utility for encryption and decryption of files and streams in Linux [CentOS 7]. It is a light weighted tool and available in EPEL repository (Extra Packages for Enterprise Linux) for Cent OS 7 and RHEL.

Monday 5 November 2018

How to install Ccrypt in CentOS 7 / RHEL 7



Ccrypt is a command line utility for encryption and decryption of files and streams in Linux [CentOS 7].

Sunday 4 November 2018

How to add Linux Host to Nagios Monitoring Server in CentOS 7



Nagios plugins and NRPE are available for Cent OS 7 and RHEL in EPEL repository (Extra Packages for Enterprise Linux).

How to create separate system user account in AWS EC2 instance



Login to the instance and switch to the root user:

How to Generate SSH Keys pairs using command line in Centos 7



Ssh-keygen is command line tool for creating authentication key pairs for SSH Key based authentication. Private Key is used for client and the public key need to upload on server.

How to Use Screen command in Centos/RHEL



Screen utility allows running multi-tasking environment and keeping processes running in the background. By default, package is not available in CentOS distribution. Follow the below article to installed.