Showing IP addresses and physical MAC addresses connected to active network interface

DOS utility ( Address Resolution Protocol ):
arp -a

setting up JSP tomcat server on linux apache

http://articles.sitepoint.com/article/jsp-quick-start-guide-linux/3

linux startup commands

To run commands automatically on starting Linux machine ( Redhat build ), add the commands to /etc/rc.d/rc.local

Forcing virtual machine shutdown

virsh destroy

Fixing Aventail VPN software failure to connect

Aventail VPN frequently fails to connect to vpn network after starting and stopping couple of time.
The only solution was to restart the computer.

in order to fix that try the following commands in DOS session:
ipconfig /release
ipconfig /renew

Other solution ( not verified )
The solution is to restart the "Network Location Awareness (NLA)" and "Aventail" services

You can save run the following commands in a batch file and run it:
net STOP Nla
net START Nla
net STOP NgVpnMgr
net START NgVpnMgr
ipconfig /release
ipconfig /renew

Networking: Changing routing default gateway

Use route command to change the default gateway. It could be useful if connecting through a VPN and you don't want to use the VPN default gateway

Here is the command:
route change 0.0.0.0 mask 0.0.0.0 192.168.1.1

Latest Whois database GeoIPCountryWhois.csv

This database contains IPAddress to Country look up table.
It is updated on monthly basis and could be downloaded from several web locations.
Here is a good download server:
http://geolite.maxmind.com/download/geoip/database/