Router Sending Out Packets?

[SteveC]

I have an interesting problem I just discovered. I have a D-Link DI-704 Cable/DSL Router that whenever it's hooked up to my cable modem, the activity light on the modem and the WAN light on the router flash almost constantly. The LAN light going to the PCs doesn't flash. This happens even if I have no PCs hooked up to the router. I've tried having nothing connecting to the cable modem, having my old hub instead of the router connected, and have a PC connected directly to the modem. Under all three of these, the activity light doesn't flash constantly.
Now, my question is: How do I find out what is going on between them? I'm fairly certain this has just started recently (I noticed it after I set up the UT2003 server). Thinking it was a setting I had changed, I reset everything to the default, and it still happens. There is nothing unusual showing up in the router log. Anyone have any ideas?

Steve

 

[Cliptin]

My best guess:
It will take a hub in between the router and the modem with another NIC attached to the hub. This other NIC should be capable of promiscuous mode and the computer containing the NIC will have a sniffer installed.

 

[SteveC]

Thanks, I'll give that a shot. Do you know any good free packet sniffers?

Steve

 

[i]

I got a DLink DI-604 cable/DSL firewall/router/switch for my sister a couple of months ago.

If your DI-704 is anything like the 604, then it might be that the 704 is trying to synchronize its internal clock with an NTP time server. The 604 tries very hard to determine the correct time for the sake of making the event/activity logs a bit more useful.

With the 604, there was an option for a user-defined time server (I used the IP address of a Navy NTP server to A) reduce the likelihood of the server being down, and B) no name to be looked up). However, if the 604 was unable to contact the specified NTP server, it seemed to have an undocumented internal list of fall-back NTP time servers to check. I think there was also an option to indicate how often the clock should be synchronized.

I have no idea if any of that is helpful. One other thing: on the 604, in the logging section, there was an "Advanced" button that lead to a section where you could enable logging for a few things not covered normally, including diagnostic information, etc.

 

[SteveC]

The DI-604 is a much newer model, and it appears that it doesn't hide the advanced features as much as the DI-704. I was unable to find any diagnostic info for it, and the manual is useless. The time synching is something I didn't think about and that could be it. I have a feeling it's harmless, but I'd rather be sure.

Steve

 

[SteveC]

It seems it's a problem with my ISP. Other people have the same problem over at DSLreports. Here and here. Oh well.

Steve