## 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