You can use the terminal command traceroute (tracert on Windows) to see what routers a packet follows from your computer to my server as follows:#374•
In the first window, we'll use the tcpdump command to print out each packet that is sent from your computer to my server as follows:
sudo tcpdump -nn host 46.22.130.125#375•
TTT Part 26 of n — DHCP
Finally, ipconfig can be used to show the DHCP ACK packet that was used to configure a network interface (again replacing enX with the actual interface you want to get the packet for):
sudo ipconfig getpacket enX#371•
TTT Part 27 of n — DNS
On most Linux and Unix OSes, DNS resolution is controlled using the configuration file /etc/resolv.conf.
This file is present in OS X but is used as a way for the OS to expose the settings to scripts and command-line utilities rather than as a way of controlling DNS configuration.
The file on OS X is in the identical format to the ones on Linux and Unix.
You can have a look at this file with the command:#364•