Grep Command

Grep Command

some examples of grep command:

* Print Apache’s documentroot directory name:

$ grep -i documentroot /etc/httpd/conf/httpd.conf

* View file contents without comments and empty lines:

$ grep -Ev “^$|^#” /etc/my.cnf

* print only IP address assigned to the interface:

$ ifconfig eth0 | grep ‘inet addr:’ | cut -d’:’ -f2 | awk ‘{ print $1}’

* How many email messages sent for a particular date:

$ cat /var/log/maillog | grep “status=sent” | grep “May 25” | wc -l

* Find out a running process/daemon from process list (thanks to staranneph for recalling this):

ps -ef | grep mysql

* You can also note cpu/mem usage by using above. like in below command output, you can see that Plesk’s statistics process is utilizing more than 18% cpu alone:

[root@myserver ~]# ps aux | grep statistics
root 8183 18.4 0.0 58384 2848 ? D 04:05 3:00 /usr/l