Editing Shell Commands (section)

== Networking ==

[http://www.cyberciti.biz/howto/question/man/tcpdump-man-page-with-examples.php tcpdump] man page with examples

<pre>sudo tcpdump -D (list interfaces)

(end with Ctrl+C)

-i (interface, use 'any' for all)

-n (disable name resolution)
-nn (disable name resolution and port resolution)

-T radius 
-T vxlan

-A (Print each packet (minus its link level header) in ASCII. Handy for capturing web pages.)

-v (-vv or -vvv, verbose mode) 

udp

sudo tcpdump -i <interface_name> udp and port <port #> -s0 -vv -X (what is S)

-s (snaplen) Snarf snaplen bytes of data from each packet rather than the default of 262144 bytes.

-X When parsing and printing, in addition to printing the headers of each packet, print the data of each packet (minus its link level header) in hex and ASCII. This is very handy for analysing new protocols. In the current implementation this flag may have the same effect as -XX if the packet is truncated.

-XX When parsing and printing, in addition to printing the headers of each packet, print the data of each packet, including its link level header, in hex and ASCII.</pre>

[https://www.commandlinefu.com/commands/view/4371/see-entire-packet-payload-using-tcpdump See entire packet payload using tcpdump]

=== Firewall ===

[http://www.cyberciti.biz/faq/rhel-fedorta-linux-iptables-firewall-configuration-tutorial/ iptables firewall configuration tutorial]

Linux Home Networking [http://www.linuxhomenetworking.com/wiki/index.php/Quick_HOWTO_:_Ch14_:_Linux_Firewalls_Using_iptables Linux Firewalls Using iptables]