cancel
Showing results for 
Search instead for 
Did you mean: 

How do I use my 2 IPs?

N/A

How do I use my 2 IPs?

Hi

I have 2 ADSL accounts, A BT Business and a Plusnet Business. On both accounts I've been allocated a pair of IPs.

My BT setup looks like this

Router WAN: Dynamically assigned IP address that changes every time
NAT Function: Disabled
Router LAN: IP address number 1
[HUB]
PC IP: IP address number 2
Gateway: IP address number 1

The above makes sense and works, my PC is visible to the outside world on it's own IP address.

How do I get my 2 IPs from Plusnet to work? It doesn't work like the above because the Router WAN is assigned IP address number 1 using DHCP, so how do I get my PC to function with IP address 2? I've tried asking Plusnet but they don't support IP ranges, I've got to Google it (their words). All Googles I've done result in a config identical to the BT setup.

Eventually I have an ethernet VPN server which will be replacing the PC. The device doesn't work behind NAT or DMZ (at least not without Double-NAT issues cropping up all the time)


Cheers J
5 REPLIES
Plusnet Staff
Plusnet Staff
Posts: 12,169
Thanks: 18
Fixes: 1
Registered: 04-04-2007

How do I use my 2 IPs?

Hi,

The diagram on here shows how you allocate the IP's.

In most cases it should just be a case of statically assigning the router's LAN address and disabling NAT, and statically assigning the IP to the PC, both with the subnet mask 255.255.255.252. Both the routers WAN and LAN IP's will both be the same.

Which router are you using?
N/A

How do I use my 2 IPs?

Hmmm, the chap I spoke to insisted you had no online help pages for this.

The router is a plain old connexant (actually it's a rebadged connexant) with the usual connexant interface you see on the thousands of routers you see out there with the connexant chipset Smiley

The BT method makes perfect sense to me. The method shown by the diagram doesn't, i.e. you allocate the same IP address manually to your LAN address that has already been allocated by DHCP to your WAN address. Unless you introduce some kind of DHCP spoofing (aka ZipB or IP Passthough) which to me would overly complicate the config and provide your CS dept with a nightmare to support (hold on this actually be the reason the chap was so adamant that they don't support it).

Still no further on. The BT setup is waaaaaay simpler Smiley

Cheers
Plusnet Staff
Plusnet Staff
Posts: 12,169
Thanks: 18
Fixes: 1
Registered: 04-04-2007

How do I use my 2 IPs?

We used to use the BT way when I worked at Freeserve, although I think the way we do it is actually better and easier.

When I've set it up it has just been turn off NAT and set the appropriate IP's, submet masks and the default gateway for on the PC as the router IP.

So router LAN IP gets - 2nd IP in 4 block with subnet mask 255.255.255.252
and PC gets - 3rd IP in 4 block with subnet mask 255.255.255.252 and default gateway as the 2nd IP in the block.
N/A

How do I use my 2 IPs?

Hokey. I'll give that ago.

<mutters something about it still not making sense Smiley >
N/A

How do I use my 2 IPs?

Cheers DT it works.

Now too sure how it works but it works nevertheless.

Cheers

J