Troubleshooting IPTables

• Use tcpdump to see if packets are making it into or out of the interfaces

• tcpdump -l -n (turn off name resolution) -i (interface name) options

• Important options:

  • Host or net x.x.x.x
  • ether host xx:xx:xx:xx:xx:xx
  • ip proto (IP protocol)
  • Port

• Read the man page

• Do we want tcpdump on the PEP's?

Notes: