How to Setup Dymamic DNS on a Double NAT Network using 2 Routers?

[msjpt]

Hi,

On my small office network i have 2 routers on my network. One is from my internet ISP provider and the other one is my own personal Draytek 2130 router, that is who managed all my internal office network. In a simple way my ISP router is there only to pass internet signal.

First problem that I have is that my internet provider does not allows for dedicated ip’s, so I have dynamic ip.

Second problem that I have is that my ISP router does not allows to be set just as a modem or in a bridge mode. So what I have done was to connect it from LAN to my Draytek WAN and then I activate DMZ on my ISP router putting there my Draytek router IP.

Now I have a NAS server inside my network who I need outside access so I need to setup a Dynamic DNS service and I have chosen Dyndns and I want it to be setup directly on the router.

Regarding this I have one question:

1- Both my ISP and my Draytek routers support and have available on their Administration page the option to activate Dynamic DNS with Dyndns. So should I setup the Dyndns account only on my Draytek router, or just on the ISP router or on both?

I appreciate anyone who can advice me on this.

Thanks

 

[thiggins]

Set up dynamic DNS on the internet connected router. That is the one that will have a routable IP address.

 

[msjpt]

Set up dynamic DNS on the internet connected router. That is the one that will have a routable IP address.

Hi thiggins,

Thanks for the advice. I will setup Dyndns on the ISP router. Then i will activate DMZ on the ISP router to point to the IP of my Draytek router. This is needed, correct?

Also, after i activate the DMZ, is there anything else i have to do in order for Dyndns to work properly? Like open some ports, or, etc..?

Thanks

 

[thiggins]

Thanks for the advice. I will setup Dyndns on the ISP router. Then i will activate DMZ on the ISP router to point to the IP of my Draytek router. This is needed, correct?

Correct

Also, after i activate the DMZ, is there anything else i have to do in order for Dyndns to work properly? Like open some ports, or, etc..?

You will need to open whatever ports on the Draytek your NAS requires.

 

[Cloud200]

There is another way to do this.

get a router the supports tomato inside the network.

one of the options is to use an external ip address checker for DDNS.
set it up and let it run.

 

[Nerre]

The point is that the "inner" router will not notice when the WAN gets a new IP-address.

_When_ it updates, the address will be correct if using an external source to get the IP, but updates might be delayed. That's why it's generally better to have the dynamic DNS client running on the machine that gets the external address by DHCP. That way an update will be triggered as soon as the IP address changes.

 

[CaptainSTX]

There is another way to do this.

get a router the supports tomato inside the network.

one of the options is to use an external ip address checker for DDNS.
set it up and let it run.

This option works very well and I have never noticed a lag. There probably is one but my ISP changes my public IP so infrequently that I never have experienced a time when I could not access my double NATed router running Tomato.