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disorganized cisco router config notes

the only interface that can have an IP directly assigned is the WAN interface.

the others have to be added to a vlan, then you make the vlan interface up using

no shutdown

and you have to bring the individual LAN interfaces up too

with a WAN IP of: 1.2.3.4/32

and a LAN of: 192.168.1.1/24

access-list 1 permit 192.168.1.0 0.0.0.255

so that thing that looks like a backwards netmask isn't a bug.

when you finish editing from terminal, make sure to copy the running config onto the startup config using:

copy running-config startup-config

to get into configuration use these two commmands:

enable
configure

You can then use

interface

to pick an interface to configure.

I had my WAN interface set to DHCP but it wasn't getting an IP

even after doing

shutdown
no shutdown

on the interface multiple times.

it took a reboot (after saving) for it to grab an IP

to forward only a single port do soemthing like:

ip nat inside source static tcp 192.168.1.2 6697 interface FastEthernet8 6697

to forward all ports do:

ip nat source static 192.168.1.2 interface FastEthernet 8

Which is what I was wanting in the first place

except that it keeps the tunnel on protocol 41 from working. :/

and to get NAT hairpinning / loopback/ whatever I followed pretty much this:

https://community.cisco.com/t5/routing/how-to-do-nat-reflection-nat-hairpin-on-a-cisco-1800-router/m-p/2754740/highlight/true#M256196