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SMCD3G with dynamic IP

I have Comcast buisness internet with dynamic IP I am having some issues with it and my Sonic Wall.
I just got a D3G and it is no longer working the same way that my older 8014 did.
I want the SMC to pass everything to the Sonic Wall. I had that setup with the 8014, however I forgot to write down my settings before they switched it out. Right now when I hit my WAN IP I get the SMC login page. I should be getting my Sonic Wall login page.
Here is my current config

Internet --> SMC --> Sonic Wall --> LAN

WAN IP (I do have the .116 if that needs to be used)
Sonic Wall external int (static)
Sonic Wall internal int (static, it then hands out DHCP etc)

On the SMC I have the following set
Disable Firewall True static IP Subnet Only
Disable Gateway Smart Packet Detection
Disable Port Forwarding
DMZ Disabled
1-to-1 NAT disabled
DHCP is off

I called Comcast and they said it needs to be in bridge mode. (Well it is not really bridge mode) but sure change it.
They do and say it is all working. I am still getting my SMC page when I hit my WAN IP though.

Is there something I am missing here? I have tried searching the forums and nothing I have tried works. My Sonic Wall has not changed since the switch over so something is not set right on the D3G.


Marlton, NJ
I don't think it's possible for you to put the SMC D3G into bridge mode without a static IP. It's definitely not possible for the end user to do it, and in the past Comcast has said it's not possible for them to make it a bridge for dynamic IPs.

I'm a little confused by your post, however. You say that you have an x.x.x.115 IP, but also an x.x.x.116 IP? Unless you purchased a static IP package, I don't see how it would be possible for you to have any say in what IP you get, or how you can even have multiple to choose from.

If you have a dynamic IP, you're better off either requesting an SB6120 from Comcast or purchasing one online.


I can't choose what IP I use, but like some people have said even with dynamic IP they also get a second address that is +1 from their dynamic. I tried 1-to-1 nat with that address, and it redirected to my modem so I could use that IP on my sonic wall, however it did not work right.

Could the 8014 be set to bridge mode? Because before getting the D3G it was acting like it was in a sort of bridge mode. When I hit my WAN IP my Sonic Wall responded, not the SMC. Did some feature or function get taken out of the D3G so that would no longer work?


Marlton, NJ
When I signed up for Business Class about half a year ago, I spent a lot of time on this forum reading years of posts regarding the SMC modems. If I recall correctly, it was actually possible to configure the SMC 8014 as a bridge on a dynamic IP. It was possible on the 8014 because the "real" admin account password was known. However, that is not the case on the SMC D3G. Although the modem "technically" supports bridging, Comcast prevents the customer from enabling the feature, and I have never of them enabling it for a customer.

Honestly, if you want to give your devices a real external IP without any BS, you should just purchase your own modem and give Comcast their trash back.


Minneapolis, MN
reply to hhahn
That is incorrect. Post in the Comcast direct forum to have them put the modem into bridge mode. I can confirm this, as I had them do this for me. They will configure it, and then you will have to reboot it and it will be placed into bridge. Works great!


Thanks, I'll give that a shot.
Once it is in bridge mode, I should just set my Sonicwall external int as DHCP correct?

Ann Arbor, MI
·Comcast Business..

1 edit
reply to feffrey

Might be a good time to swap for a moto SB6120

After the $7 charge appeared on my bill, I purchased an SB6120 (~$75). It passes the public IP to my router via DHCP. (Dynamic DNS finally works on my router too). The SMC is fine for static IP's, but you might consider the SB6120 unless you still get a free SMC.


Minneapolis, MN
reply to feffrey

Re: SMCD3G with dynamic IP