Public IP NAT passthrough?

Hi Ya’ll.

I’m having a hell of a time trying to get a downstream MT to take a public IP address from our main MT Router. Our system is as follows:

2 T1 lines (internet) bonded by a cisco 2130 router using Multilink to bond the serial interfaces.

Out of the cisco using an X-Over cable to our MT PC Ethernet 1.

Out of the MT Router to a Canopy 2.4ghz AP.

2.4ghz Subscriber Module on the other end.

Out of 2.4ghz SM to RouterBoard 532a

I’m trying to get it set so the RB 532a will take a public IP address from our pool. Then assign seperate ip’s from an internal IP Pool. In essence acting as a new MT Router a seperate system.

Problem is, when I give the RB 532a a static IP address in our public pool, it will not feed internet. It’s as though it’s not even connected.

here is a diagram of our system.

Any help appreciated.

Mac

Mactrekr -
I have never used the Canopy system so you’ll have to forgive my ignorance there but typically you would just tell your main router (your home site MT in this case) to route the public ip address/subnet mask to the canopy AP. The canopy AP will have to have a static route put in it to tell it to route your pubilc ips to the canopy SM. The SM needs a route to send the public IPs to the ‘new’ MT RB 532a. Here I do not know if you are either assigning private IPs to cpus behind the RB 532a or you are assiging public IPs to cpus behind the RB 532a… You’ll need to tell us that…

The above should get you pointed in the right direction - come back if you still need help…

Thom

OK so imo i belive you should setup dhcp server on the local and remote end and have a dhcp client on the remote end to grab the public ip from the main ap and then the dhcp server on the remote end can hand out local address 192.168.0.2-253 and such, make sure you have masqarading setup if you want to use it , and that you add default gateway and use client dns setting put into your dhcp servers
mainapdhcp server >> remotedhcpclient = public ip
remotedhcpserver >> local network = private ip address
make sure the gateway is set to the mainap on the remote network
May have to use masqarading as well

Thom,

I plan on using dhcp to hand out private IP’s to the devices behind the RB532a. Canopy, for all intents and purposes doesn’t have much to do with the system. From what I can discern, in our configuration, we have the canopy set up a a “wireless ethernet” cable. Canopy Subscriber Modules don’t even show up in the MT. I can very successfully have our primary MT, (x86 box) assign IP’s via DCHP to any downstream device and can even NAT a public IP to that downstream device. My problem is that when I try to NAT again from the RB532a to a device behind the RB it doesn’t work.

Mac

Ok then you need to add routes , either src-nat dst-nat for the network or use masqarading , look up hot-spot masqarading and it will show you how to do it, and yes you cant nat without either src-nat dst-nat or masq enabled , imo masq is way easier

Nate,

Could you explain how I could accomplish this via masquerade? Doesn’t make any sense to me.

Mac

ok if your private lan is 192.168.0.0/24
and you have a public pppoe connection or any other kind of connection and you want to nat it then the easy way is to add a firewall rule

/ip firewall nat add chain=srcnat action=masquerade
would masqerade all traffic from your local lan to your gateway on the remote network

you can tighten down this rule as well

/ip firewall nat add chain=srcnat src-address=192.168.0.0/24 action=masquerade

or

/ip firewall nat add chain=srcnat src-address=192.168.0.0/24 out-interface=outinterfacenamehere action=masquerade

These all accomplish the same thing with some being more secure and functional for different environments
change the src-address to the address range of your local lan

Hope this helps