Modem-router won't assign addresses; attached router will

[varxx]

Just got fiber optic. Nice.

The Huawei HG8245h modem-router given me by the ISP has four LAN ports.

(1) I hooked my desktop up to LAN1 of Huawei modem-router. Worked fine. Good ethernet connection, pretty good wifi from Huawei modem-router.

(2) To see if I could get better wifi, I hooked up my Apple Airport Extreme wifi router to LAN2 of the Huawei modem-router. It can't connect. Error message: NO DNS SERVER.

(3) Next I disconnected my desktop and I hooked up Apple Airport Extreme to LAN1 of Huawei modem-router. No Internet.

(4) Through trial and error, I set router mode on the Apple Airport Extreme to Bridge Mode and got it working.

(5) Then I connected my desktop to LAN2 of the Huawei modem-router. No Internet. Error message: NO DNS SERVER.

(6) Finally, I connected my desktop to one of the LAN ports of Apple Airport Extreme. Connection!

So, now I have my Apple Airport Extreme managing my LAN entirely, both wifi and ethernet. Speed is very good with both.

I should be happy, but I'm not. I want to understand why I can't have both my desktop and my Airport Extreme connected to LAN ports on the Huawei modem router.

MY QUESTION: I want to know why I can't get my ISP modem-router to assign any additional DNS addresses. It can assign only one. Do I need to change settings in my Huawei modem-router setup?

Thanks!

 

[Samir]

Are you sure that you're getting an IP address at all from the second LAN? On our Charter business SMC branded modem/gateway, only port 1 will assign an IP and the others don't really do anything. Sounds like this is set up the same way.

 

[TonyH]

Are you sure that you're getting an IP address at all from the second LAN? On our Charter business SMC branded modem/gateway, only port 1 will assign an IP and the others don't really do anything. Sounds like this is set up the same way.

Time to talk to ISP tech support. Sounds like only LAN1 is used?

 

[Samir]

Time to talk to ISP tech support. Sounds like only LAN1 is used?

Yep, when the modem's built-in router is disabled and it's in 'modem-only' mode, only lan1 issues an IP. You can connect a switch and get additional IPs like normal, but the other ports basically don't do anything beisdes show a link light.