Linux Basics

Q. How do I list or display the permission of a file using ssh? I don’t have GUI installed on a remote Linux computer. A.You need to use ls command with -l option. File access permissions are displayed in the first column of the output, after the character for file type. ls command List information about the FILEs. If no argument …

mysqldump is an effective tool to backup MySQL database. It creates a *.sql file withDROP table, CREATE table and INSERT intosql-statements of the source database. To restore the database,  execute the *.sql file on destination database. Using mysqldump, you can backup a local database and restore it on a remote database at the same time, using a single command. In …

Crontab command manages the cron table that is used by the cron daemon to execute the cron jobs. This article explains the various command line options of the crontab command.   1. Tweaking Other Users Crontab using Option -u -u stands for user. This should be followed by a valid username in the system. -u option alone doesn’t do anything. …

I’ve installed memcached server under Linux but it is still showing old data. How do I flush the contents of a Memcached instance / server? You can invalidate all existing cache items using the flush_all command. This command does not pause the server, as it returns immediately. It does not free up or flush memory at all, it just causes …

Question : How to turn off password expiration under Linux?   Answer: The  Encrypted password list is stored  in /etc/shadow file cat /etc/shadow   root:$1$dkk&Iw6zvgu$P3ms0o5GiXv66BzNXe0:15294:0:99999:7:: This is the explanation of the above line {userName}:{password}:{lastpasswdchanged}:{Minimum_days}:{Maximum_days}:{Warn}:{Inactive}:{Expire}: Under Linux, to turn off the password expiration  we  use a  tool   called “chage” you  can  download it via yum  or  apt-get package  managers  tools. For Debian based …

How do I use grep command in Linux operating systems? Can you give me a simple example of grep command? The grep command searches the given file for lines containing a match to the given strings or words. By default, grep displays the matching lines. Use grep to search for lines of text that match one or many regular expressions, …

How do I delete or remove a single file from within a tar ball under Linux operating systems? You can use the following syntax to delete a file from a tar ball:   tar --delete -f example.tar filename Example: Delete a File From a Tar Ball First, create a tar ball for testing purpose using the tar command, enter: # cd …