Below are a few network-based utilities available with Ubuntu. The screen captures below are from Ubuntu version 10.04. The wget command allows HTTP access via a terminal prompt.
The tracepath command is similar to traceroute, but does not require root privileges. The command attempts to trace the “hops” to the destination specified.
The mtr command attempts to combine ping and tracepath. It shows the ping times for each “hop”.
The host command performs DNS lookups.
The dig command can be used for DNS lookups as well.
The whois command displays the whois records for the domain in question.
The ifplugstatus command will display if a network cable is plugged into an interface. It is not installed by default with Ubuntu, but the command sudo apt-get ifplugd should install it. The text “link beat detected” means a connection is present.
The ifconfig command will display information for all network interfaces, including IP addresses and MAC addresses.
The dhclient command will release and renew a DHCP lease. The –r parameter will release the current IP address.
The netstat command will display general information interface statistics. The –p parameter will display the programs associated with open sockets.
The command netstat –na | grep –i listen will display the network listening ports.