The Missing Link

[tmoulder]

Hi All!

I'm working with Arkadi Samarov's 570 DHCP program and trying to pull and IP from my company servers. I had this working a couple of days ago, but when I went back to play further, it won't connect.

Here's the funny part - the PLC is not showing a link. I plug it into my computer, and the link shows up, but the corporate router is a no-show, like the cable is not plugged in at all

I'm trying to find out if a router can outright refuse a link - I thought this was a purely electrical signal, and had no dependency on IP or anything else, but looking online for the word "link" throws up too much static for a meaningful answer.

Anybody see anything like this in the past?

Thanks,

TM

[linxchas]

Here is a document from Fluke networks with explanation how network link works:

Fixing Ethernet and Fast Ethernet Link Problems

One of the issues you may have - is recently (last 4 years) added feature to cysco and some other switches called: "Unidirectional Link Detection"