Telnet
The usefulness of Telnet in troubleshooting comes
from its ability to connect to a specific destination port on a remote server,
allowing it to be used to confirm correct traffic flow from a client to remote
server. Telnet is particularly useful for transport layer diagnostics.
Telnet can be run as either a command line utility or with a GUI. Figure
shows the
command line Telnet application being used to confirm connectivity to a POP3
server.
ipconfig Command
The
ipconfig /all command can provide the network engineer with
a lot of information about the configuration of a Windows-based machine. This
information covers details from the MAC address at Layer 2, the IP address at
Layer 3, NetBIOS information at Layers 4 and 5, to DNS information at Layers 6
and 7.
