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Comcast gear in bridge mode, port forwarding on my router doesn't work

Contributor

Comcast gear in bridge mode, port forwarding on my router doesn't work

I had a dumb Comcast modem. I had a Netgear WNDR3700v3 plugged into it, and I had port forwarding set up on the Netgear. All worked as desired.

 

Comcast replaced my modem with an Arris TG1682G. I put the Arris into bridge mode, and didn't change the Netgear's configuration. Port forwarding doesn't work.

 

If I put the Arris back into router mode, I can forward ports to the Netgear. The Netgear then forwards the ports properly.

 

I've done a lot of testing, and it seems that traffic is not getting past the bridge.

 

I spent a lot of time with Comcast support, but eventually we decided we were running in circles.

 

Does anyone know where I've gone wrong?

Tags (1)
Silver Problem Solver

Re: Comcast gear in bridge mode, port forwarding on my router doesn't work

You didn't say, so it's worth asking. Do you have the Netgear connected to port1 in bridge?

Contributor

Re: Comcast gear in bridge mode, port forwarding on my router doesn't work


Paraniod wrote:

You didn't say, so it's worth asking. Do you have the Netgear connected to port1 in bridge?


Yes.

 

Good question.

Silver Problem Solver

Re: Comcast gear in bridge mode, port forwarding on my router doesn't work

OK then, have you tried a quick 2 sec press of the reset button, with the Netgear connected. In bridge the gateway acts like a straight modem of course and has to be powercycled or reset whenever the device directly connected is changed.

 

You may have already tried that of course. Just saying.

Frequent Visitor

Re: Comcast gear in bridge mode, port forwarding on my router doesn't work

I am having the same trouble with port fwd.

The TG1682 seems to work well with wifi, wired etc.. Good speeds and connection just port foward'nd blows.

 

I was trying to port fwd only thru the 1682 with no luck so I bought a Netgear AC3200.  Enabled bridge mode and opened ports on the Netgear.  Still no access to those ports.

Also I seem to motice when in bridge mode my speed drops from 125mb to 50mb...  No idea there.  Main focus is port fowarding.

 

Any luck on your end?

 

Contributor

Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

Actually, I did get everything working. Although I never was sure I identified what caused the problem, I did get it to go away. The key seems to have been resetting the gateway to "factory" state, and working from there. If you don't want to use your internal router, then you don't want your gateway in bridge mode.

 

Here is the procedure that should do it:

 

  1. Make sure you know your desired configuration, primarily your WiFi network names and passwords, before re-initializing the box. While you could, in theory, restore a saved configuration I chose not to do so.
  2. To reset the gateway to its original as-shipped state, press and hold the reset button (use a paperclip in the little hole in the back, it's labelled) for 30 seconds. Any shorter time, and it merely reboots the box.
  3. Connect a PC directly to the gateway and use its management tool (http://10.0.0.1) to set things the way you want.
  4. Make sure your PC can see the wide world.
  5. At this point, the gateway will have a routable IP address on its WAN interface. Your PC will have an address like 10.0.0.x (a non-routable, LAN-only IP address that begins with either "10" or "192.168").
  6. If you want to use it in bridge mode, it's probably unnecessary to worry about passwords and the like; but I did, anyways.
  7. Make sure you have a firewall in place on your PC before this next bit, or you could have a malware infection within seconds.
  8. Remember this crucial fact: once the gateway has been put into bridge mode, you won't be able to talk to it at all. If you change your mind, you'll have to re-initialize it again.
  9. After putting the gateway into bridge mode, do whatever it takes (a reboot of your PC should do it, if necessary) to make sure that your PC can still see the Internet. At this point, your PC will have a routable IP address (something beginning with other than "10" or "192.168") and will be out there naked.
  10. Once you're proven that your gateway is functioning as a bridge, disconnect your PC and plug in your router.
  11. Plug your PC into your router.
  12. Although there are some shortcuts, I've had the best results over time by rebooting each piece. WIth modern gear, it shouldn't matter; but I've found it best to start with the WAN end and work inwards.
  13. Check your router to make sure that it is connected to the Internet (not merely physically connected to the gateway). It should have a status indication somewhere in its own management interface, and you should see that its WAN address is routable (as described above). If your router can't get out, wait a few minutes and reboot first the gateway and then the router.
  14. At this point, both your router and your PC(s) should be able to see the world.
  15. If that was your intent, set up port forwarding on your router.

 

By the way, your router's IP address will not be the same as the address your gateway originally had. That threw me for a loop, at first.

Frequent Visitor

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

I will give this a shot.
I did most of these steps. No luck.
I will try one more time tomorrow.

How about your speed in bridge mode?
When I reset the modem in bridge mode with my main pc still connected. My speed dropped from 125mb to 50mb.
Was not my concern at the moment but still did appear that way.
Contributor

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

I'm not sure what to tell you about my speed, because I didn't do a before and after test. I'm getting 29+Mb down and 6+Mb up. That's seems pretty good, but everything depends upon what you're paying for. You're evidently on a faster data plan than I am.

Frequent Visitor

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

Jerry..Thanks man!!!!

I have sucecess.

Well I am ended up going though the TG1864 Comcast modem.

I followed your instructions.

The master reset(hold for 30 sec) I think was a big factor.

I then went into bridge mode. While PC still wired I was able to see the net.

I then did a port checker and the ports I checked were open.

 

Then proceded to hook up the Netgear router.  and fwd'd the ports I wanted open.  Did port checker while on the netgear and my specific ports were still open.

 

I said let me try one more time wiht the TG1864.  I did a master reset(30 sec hold)

Logged into the UI and setup my wifi password etc and then went to adavanced to fwd my ports.  Did a port checker and all was good.  I was stoked.  Its been almost 3 mths of messing around.

Thanks again!!!

 

 

Frequent Visitor

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

Going to return the netgear. 

I was very happy with the speed and wifi with the comcast modem.

 

For some reason in bridge mode my speed would throttle way back to like 40-50mb.....vs 125mb.

Even with the PC connected directly to the comcast modem in bridge mode.

Not sure the issue there.

 

 

Contributor

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

I didn't do any speed testing.

 

I am still using my Netgear, because I like the degree of control it gives me. I turn the guest network on only when guests need it.

 

As I understand it, when the Home Hotspot is enabled it is really only available to other Xfinity Internet customers at certain levels. That would exclude my brother, but include passers-by. The Netgear's guest network gives me the choice of who can or can't use it.

 

I have also, at times, forced a channel selection. I'm not sure that made a big difference, but with my physical layout anything helps.

New Poster

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

What you described perfectly worked for me. Steps

- change xfinity modem-router to bridge mode

- connect your router to port 1 in xfinity router

- power down both routers

- start routers

- now your router has external IP instead of 10.0.0.x

- your port forwarding is accessible from extranet now!

 

Thanks!

 

Diamond Problem Solver

Re: Resolved: Comcast gear in bridge mode, port forwarding on my router doesn't work

Year and ahalf old dead thead now being closed.