Theres your port and the protocol beeing used.. If you like to see it as it's port value, you could try adding the
-n switch.
Use the
-v switch to see a more elaborate output, like which interface it's bound to, and how many packages the rule has captured.
By the way the
dpt is shorthand for destination port, and as we all know,
webcache is port 8080, so now any connection on port 8080 comming to your EXTERN_NIC will be redirected to port 8080 on the machine located at 172.17.0.49.
But repearting the rule is redundant, since the first one will capture any match befor even reaching the second one...