Skip to content
PuppyDishSat's profile

Visitor

 • 

4 Messages

Friday, January 16th, 2015 2:00 PM

Ethernet connectivity Dying - Might Need Bridge Mode?

Hi,

 

My company recently had a new service installed, and we are experiencing some trouble.

 

We have 5 static ips, and are currently only using one on a gateway appliance connected to a MODEL DPC3939B Cisco Comcast modem. The service is working great, but occasionally it seems that the traffic passing between the gateway IP (Modem) and our Appliance drops to almost nothing (Less than 20Kbps) and stop passing any communicable traffic. If I reboot the Comcast modem, it picks back up and everything is fine. We have already had Comcast place the modem in Virtual Bridge Mode, which apparently turns off the firewall and DHCP, but that has had no effect.

 

My next thought was to ask to have the Comcast modem put in true bridge mode, but I wasn't sure if that was possible with a static IP?

 

No Logs that I have been able to find are catching the issue on our side or comcast's because the traffic doesn't completely give out. Any help appreciated.

 

Thanks.

Advocate

 • 

1.4K Messages

10 years ago

Hello PuppyDish Sat and welcome,

 

I recommend that you first check your Appliance Configuration and make sure that Load Balancing is disabled. This can cause the exact issues that you are expereincing. Next, if you could log into you DPC and provide a copy of your channels bonding downstream and up stream SNR and Power levels, this would enable us to know if you have and cabling or interconnection signaling issues.

 

Comcast Gateways do not work in TruBridge Mode (TBM)utilizing a staticIP. This is due to TBM disables all DPC routing and only operates in pass-through mode, which does not support the routing aspects of your Static IP. Per your disabling your DPC DHCP this is the best way to avoid any DHCP Server conflicts between your Appliance and the DPC. 

 

Look forward to hearing from you for further assistance.

Visitor

 • 

4 Messages

10 years ago

Thanks very much for your reply and assistance!

 

Where can I check to see if my modem has Load Balancing turned on/off at? I checked all through the menu structure (on the customer facing 10.1.10.1 side) and couldn't find any setting for Load Balancing or bandwidth management.

 

Here are my SNR results..

 

IMG_6758.PNGIMG_6759.PNGIMG_6760.PNG

Advocate

 • 

1.4K Messages

10 years ago

Fyi, I was referring to your Appliance Configuration  not the Comcast Mode.

 

Visitor

 • 

4 Messages

10 years ago

Oh, OK, I understand.

 

On our current configuration, you are the only gateway, and there is no load balancing, firewall, or other processing going on. We simply have our static IP set to (our) Eth2, and it plugged in to your Eth1. This configuration works fine, but randomnly, the data will drop to somewhere between 1Kbps and 20Kbps and just fluctuate speed. No public traffic passes through at all.

 

As soon as I reboot the Comcast modem, it picks back up, and everything is fine until it happens again.

 

As for the CC Modem - I have turned off IPv4 and IPV6 DHCP, Firewall, etc. and ensured that our settings match that of the "Passthrough Mode" as described in the forum.

 

Did my SNR/Upstream results help any, or is there something else I can look at to determine what is happening?

 

Thanks again for your help!

 

Visitor

 • 

4 Messages

10 years ago

There is no load balancing on our side happening at all. The Comcast modem is our only Gateway, so there would be nothing to balance. Our appliance is simply being used a router to take the traffic from your gateway, and send it to a private subnet. This is working fine, until the Comcast modem and our router stop talking to each other randomnly. As I stated, if I look at the port on our side, it shows minimal activity (2k - 20k), but no real traffic (in other words, I can't even ping the gateway from our modem during this issue). If I reboot the Comcast modem, it fixes it for another random amount of time.

 

Given that we have NO load balancing happening on our side, is there a chance this could be service related, or even a bad modem? What are your suggested for next steps in troubleshooting?

 

Thanks.

 

 

 

 

 

 

Advocate

 • 

1.4K Messages

10 years ago

 

Your upstream and downstream values look fine on your Comcast Gateway.

 

What I was talking about is your original post "  but occasionally it seems that the traffic passing between the gateway IP (Modem) and our Appliance drops to almost nothing   ",  if this Appliance has load balancing enabled, it should be disabled.

Advocate

 • 

1.4K Messages

10 years ago

 

Myrecommendationistocontact800-391-3000,usetechnicaloption, provide your Comcast account #, then inform the technical agent of the issues you are having and make sure he checks all signaling paramters into you modem, can ping your modem, can ping your staticIP rputable device.  They may have to send a technician to your business to make sure your 30 day signaling levels are not marginal and causing your modem to reboot, loose service, etc.