When installing some software on AWS, the software package may ask for the DNS server ip address, default gateway IP address and the subnet mask. If you are running windows, you can simply log into the Windows instance running on AWS using RDP and issue an ipconfig command. When running on Linux, you need to issue three different commands to get the information:
1. ‘ifconfig eth0’ (Subnet mask)
2. ‘route –n | grep ‘UG[ \t]’ | awk ‘{print $2}’ (Default gateway IP)
3. ‘cat /etc/resolv.conf’ (DNS Server)