Release unused memory in Ubuntu

sometime we think that RAM is filled with running processes. But actually more over its cached by the processes which has finished its execution. We can release this cache RAM using superuser command.

first check the status of RAM by this command:


"echo 3 > /proc/sys/vm/drop_caches"

Now again check RAM using free command. You will observe too much RAM is released.

How to reset Ethernet ports on ubuntu

To reset or refresh Ethernet interface on Ubuntu use following command:

rm -f /etc/udev/rules.d/70-persistent-net.rules

this  command will reset the all Network interfaces in next reboot.

Domain name Mapping in apache Ubuntu 15.04 without “www” solved

<VirtualHost *:80>
    ServerAlias *
    DocumentRoot /var/www/
    ErrorLog ${APACHE_LOG_DIR}/error.log
    CustomLog ${APACHE_LOG_DIR}/access.log combined