January 29th, 2012, 04:34 AM
Router+Switch and DHCP problems
Holy crap he's asking a question. Damn right I am. It's 2:30am and I've spent the last few hours searching for answers to this but I can't get anything concrete - and now is not the time to take a crash course in crazy networking stuff.
So, modem connected to router. Got a wireless laptop and a wired box connected to the router and they're working fine. Got a switch: Netgear GS108T(v2). Connected it to the router and that's fine so far. It has an IP address, I can access it from the laptop, blah blah blah.
Now I've added a box behind the switch and that's not fine. It's stuck on trying to get an address from the router: I see the request get sent, the router sees and responds, but the offer never makes it back to the box. I suspect this is a symptom of larger problems which I don't know about.
What's wrong, what should I do to fix it, and/or what else do you need to know?
My best guess was blindly "tagging" and untagging ports all over the place, but that hasn't worked.
January 29th, 2012, 10:11 AM
It looks like that router has DHCP filtering that will block a DHCP server's reply unless the port the request comes in on has been authorized to receive DHCP requests.
See page 72:
That's my initial guess.
Comments on this post
January 29th, 2012, 03:29 PM
Figures it was something easy
Okay, that works - has a lease and all - but I (still) can't access anything else. Not the switch, router, or another computer on the network.
192.168.1.1 is the router; the computer knows the MAC address, the switch knows which port has it, but from there I'm not sure what's happening.
 Found it. That mass tagging I did earlier? Seems I didn't fully undo that. Sometime I'll have to learn what all it means, but for now I know that I shouldn't muck around with it because my track record has been Screwing Things Up 2, Fixing Problems 0.
Last edited by requinix; January 29th, 2012 at 04:12 PM.