Ubuntu - Networking - Cheatsheet

Command	Description
ifconfig	Display the link and address status of active interfaces.
ip addr show	Display the link and address status of active interfaces.
route -n	Display all the routing table in numerical addresses.
ip route show	Display all the routing table in numerical addresses.
arp	Display the current content of the ARP cache tables.
ip neigh	Display the current content of the ARP cache tables.
plog	Display ppp daemon log.
ping google.com	Check the Internet connection to “google.com”.
whois google.com	Check who registered “google.com” in the domains database.
traceroute google.com	Trace the Internet connection to “google.com”.
tracepath google.com	Trace the Internet connection to “google.com”.
mtr google.com	Trace the Internet connection to “google.com” (repeatedly).
dig [@dns-server.com] example.com [{a\|mx\|any}]	Check DNS records of “example.com” by “dns-server.com” for a “a”, “mx”, or “any” record.
iptables -L -n	Check packet filter
netstat -a	Find all open ports
netstat -l –inet	Find listening ports.
netstat -ln –tcp	Find listening TCP ports (numeric).
dlint example.com	Check DNS zone information of “example.com”.