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New modem / issues with ports

By Atwooooood
Feb 14, 2013
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  1. Lately I have been having some problems with people connecting to some listen servers that I try to host. I tried an open port check tool, and these ports are coming back as closed although I have opened them in my router and all settings are correct.

    I then got to thinking that not too long ago my ISP replaced my old modem (basic, single WAN port modem) with a large Arris TG862 modem which has a WAN port, along with 4 LAN ports. I found out this thing had an IP address for it, so I logged into it (couldn't do this with my old modem), and discovered this modem has all the settings that my Linksys WRT54GL router has (DHCP, Wireless capabilities, WAN/LAN setup, Firewall, etc..)

    My question is, could this new modem be the cause of my problems? I noticed that it has DHCP enabled along with the firewall which are both also enabled on my Linksys router. Any insight on this would be great, as I've been trying to figure this out the past couple days and have come up dry.

    Edit: After finding an online manual for this Arris residential gateway, it turns out that port forwarding is referred to as "Virtual server" for this device. I tried to forward the port I'm having issues with, but when I go to apply the settings, it says invalid IP address even though I am typing in the correct local IP address.

    Edit 2: While tinkering around with this thing, it dawned on me that I should be setting the Arris gateway to bridge mode, but after setting it to bridge mode and restarting the gateway like it suggests I do, my internet connection goes out.RT54GLWRT54GL WRT54GL
  2. tracker1

    tracker1 TS Rookie

    Set your Arris TG862 modem/router to previous mode (routing), keep DHCP server enabled. Disable DHCP server and firewall on your router WRT54GL. Connect the modem(Arris TG862) and router(WRT54GL) with their LAN ports.

    In the DHCP settings of your modem/router you should see what LAN IP address range it is using, forward ports accordingly(Virtual server).
  3. JC713

    JC713 TS Evangelist Posts: 6,955   +902

    Try resetting: Power off the router, then the modem, and then power on the modem and wait for it to fully power on before turning back on the router. Why in particular do you think it is the modem? Could it be the router?
  4. Atwooooood

    Atwooooood TS Enthusiast Topic Starter Posts: 115

    I understand your instructions tracker1, but I am wanting to use my router for routing, not the modem.

    And to UNKNOWN, I have done that resetting procedure already. I have every reason to think it is the modem mainly because all was working fine before my ISP switched our old basic modem to one of the modem/router combos.

    I have tried hooking the computer straight into the modem and switching it to bridged mode, then hooked the computer directly to the router and reset to factory settings, and I hook the router up to the modem after the modem has fully reset and loaded up. The router issues the first IP address in the DHCP range which to me looks like it should be working, but I have no internet access. Having windows "diagnose" the problem gives me a DNS error (which I have tried using static DNS's with no luck).
  5. JC713

    JC713 TS Evangelist Posts: 6,955   +902

    Well, maybe flush you DNS resolver cache (search: "cmd" in the start menu>then type in: ipconfig /flushdns) and try the Windows Diagnosis again.
  6. tracker1

    tracker1 TS Rookie

    You should connect your modem (bridge mode) to the wan port of you router. Can you check the status of your router's WAN port does it get any WAN IP address?


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