Usefull Linux networking commands:

* /etc/rc.d/init.d/network start - command to start, restart or stop the network
* netstat - Display connections, routing tables, stats etc
o List externally connected processes: netstat -punta
o List all connected processes: netstat -nap
o Show network statistics: netstat -s
o Kernel interface table info: netstat -a -i eth0
* ping - send ICMP ECHO_REQUEST packets to network hosts. Use Cntl-C to stop ping.
* traceroute - print the route packets take to network host
o traceroute IP-address-of-server
o traceroute domain-name-of-server
* mtr - a network diagnostic tool introduced in Fedora - Like traceroute except it gives more network quality and network diagnostic info. Leave running to get real time stats. Reports best and worst round trip times in milliseconds.
o mtr IP-address-of-server
o mtr domain-name-of-server
* whois - Lookup a domain name in the internic whois database.
* finger - Display information on a system user. i.e. finger user@host Uses $HOME/.plan and $HOME/.project user files. Often used by game developers. See http://finger.planetquake.com/
* iptables - IP firewall administration (Linux kernel 2.6/2.4) See Bakulan - Linux firewall/gateway configuration.
* ipchains - IP firewall administration (Linux kernel 2.2) See Bakulan - Linux firewall/gateway configuration.
* socklist - Display list of open sockets, type, port, process id and the name of the process. Kill with fuser or kill.
* host - Give a host name and the command will return IP address. Unlike nslookup, the host command will use both /etc/hosts as well as DNS.
Example: host domain-name-of-server
* nslookup - Give a host name and the command will return IP address. Also see Testing your DNS (Bakulan - Linux) Note that nslookup does not use the /etc/hosts file.