[SOLVED] Double DNS/NAT issue

[wurstnight]

My family and I live with my in-laws in a separate house on the property, and due to the way the in-laws are with technology, we're not allowed to have our own internet service separate from theirs. Their solution was to have our router be a second on their network, even paying extra to their ISP (from my pocket) for my router to have its' own IP. The way it's setup, I've been having an issue with double DNS/NAT and it doesn't let my connect to any Peer-to-Peer ports, therefore limiting gaming with friends/family. Does anyone have any idea how to fix the double DNS while allowing both routers to provide internet (most fixes I've seen online restrict the network access on the first router since they all assume it's an ISP required router)?

For reference both routers are Netgear and we're using a local mom-and-pop owned ISP.

 

[bill001g]

So what do you mean by " pay extra for it's own IP".

This would imply that your router was being assigned a public IP by the ISP and you should not have double NAT.

First step is to go into your router and look at the IP assigned to the wan port. This IP must be a public IP. Although you can look up the ranges it is simpler to just compare this IP with a site like whatsmyip. If they are different then you likely have a private IP.

If you have a private IP then there is no solution, but I don't understand why the ISP would then charge a extra monthly fee. It is trivial to setup a second router yourself without paying the ISP.

Depends how much you pay. There are fairly expensive VPN services that you can get a public IP and most of them it is a fixed public ip so you so don't need to use things like DYNDNS to solve the problem of the public IP changing.

 

[wurstnight]

So what do you mean by " pay extra for it's own IP".

This would imply that your router was being assigned a public IP by the ISP and you should not have double NAT.

First step is to go into your router and look at the IP assigned to the wan port. This IP must be a public IP. Although you can look up the ranges it is simpler to just compare this IP with a site like whatsmyip. If they are different then you likely have a private IP.

If you have a private IP then there is no solution, but I don't understand why the ISP would then charge a extra monthly fee. It is trivial to setup a second router yourself without paying the ISP.

Depends how much you pay. There are fairly expensive VPN services that you can get a public IP and most of them it is a fixed public ip so you so don't need to use things like DYNDNS to solve the problem of the public IP changing.

I just checked and my router is set to dynamically get the ip from ISP and it's set as the same IP as the first router even though we're paying more for a separate public IP. Gonna give our ISP a call and see about getting it fixed, thanks for the help!

EDIT: I've just been informed we're paying for a second NAT address, not a second IP. Now I'm really stumped since I'm a major noob with networking.

 

[bill001g]

If there is a NAT you do not control then there is no chance to make port forwarding work.

First step is I would see if you can stop paying the ISP for the connection and do this yourself. I guess it depends on the details but all you do is take any consumer router and plug the wan port into the router that is on the main account. You should at this point be about at the same point you are now.

If you want I would take the money you save not paying the ISP and look into a VPN service. You want one that in addition to the vpn service offers a non shared public IP. There are also vpn hosting centers where you get a small linux image running vpn and a public ip. That though is for a bit more advanced users.

 

[wurstnight]

If there is a NAT you do not control then there is no chance to make port forwarding work.

First step is I would see if you can stop paying the ISP for the connection and do this yourself. I guess it depends on the details but all you do is take any consumer router and plug the wan port into the router that is on the main account. You should at this point be about at the same point you are now.

If you want I would take the money you save not paying the ISP and look into a VPN service. You want one that in addition to the vpn service offers a non shared public IP. There are also vpn hosting centers where you get a small linux image running vpn and a public ip. That though is for a bit more advanced users.

We originally had it set up with our router just plugged directly into theirs, but before paying for a separate NAT address our house had no internet whatsoever. We were told we had to have them because of there being multiple mac addresses on the network.

Also, what do you mean by a NAT I do not control? The in-laws will let me change settings on their router as well if that's what you're referring to.

 

[wurstnight]

If there is a NAT you do not control then there is no chance to make port forwarding work.

First step is I would see if you can stop paying the ISP for the connection and do this yourself. I guess it depends on the details but all you do is take any consumer router and plug the wan port into the router that is on the main account. You should at this point be about at the same point you are now.

If you want I would take the money you save not paying the ISP and look into a VPN service. You want one that in addition to the vpn service offers a non shared public IP. There are also vpn hosting centers where you get a small linux image running vpn and a public ip. That though is for a bit more advanced users.

Would a DMZ server help with the double NAT? That's the only suggestion that my ISP's technician could come up with, but he wouldn't tell me how to set it up as he was "too busy".

 

[bill001g]

You did something really strange if the ISP could even see the second router unless you are plugging the second router into the modem.

The second router looks more or less like a pc to the main router.

So what you do is ISP----modem----Main router---(lan ports)--- (wan port)->second router----end devices.

The only thing that can bite you is if the lan network on the main router is the same as the second. So if the main router uses 192.168.0.1 for its lan you want to use 192.168.2.1 for your second router lan.

If you can make changes to the main router then you can use the DMZ option to get past the NAT issue on the main router. In that case if your main router is using 192.168.0.1 for its lan put in a static IP of say 192.168.0.200 on the second router WAN port. Then put a DMZ rule in the main router pointing to 192.168.0.200