This post will show how to port forward a single port from the internet to the internal network. You can easily use the Cisco ASA Appliance GUI through a web browser or Cisco ASDM to create a static nat and an access rule but for those that need to do it from command line here we go:
- First login to your router through ssh or telnet and use the privilege mode enable.
- Next go to configuration mode by running configure terminal.
- Execute the following commands: (In this example we will open HTTP Port 80)
access-list outside_access_in extended permit tcp any interface outside eq 80
static (inside,outside) tcp interface 80 10.1.1.10 80 netmask 255.255.255.255
access-group outside_access_in in interface outside
Type exit to get out the configuration mode
Type write to save the changes to startup-config