Very interresting networking issue (all wired)

[Demosai]

Alright....As you can tell, I'm new here, and like most everyone when they first come here, it's cause they have an issue and don't know what to do. Surprise, I'm no different XD. But unlike others, I've tried as much as I can. So lemme get started describing the issue and see where this goes.



Here's the issue, as well as I can explain it.

The Pathline
Cable from the wall goes to a Motorola cable modem
The ethernet cable from the modem goes to a Linksys 10/100 Workgroup switch port 1
Port 3 on said switch goes to a custom built desktop running Windows XP Pro SP2.
Port 4 on said switch goes to an IBM T42 laptop running Windows XP Pro SP2. (dual boot Ubuntu, but I haven't ran it under linux in a fairly long time). I recently removed Novell Client to eliminate a possible cause of the problem



The desktop runs just fine, as I am currently posting from it. This (in theory) eliminates an issue from either the cable modem or the switch. The switch has been verified good, and the laptop ethernet port works, as I can plug into a port at the library and have internet just fine.


now, here's some analysis I've already done.
Windows Live Messenger Connection Troubleshooter
Error: Default Gateway
Your gateway appears to be offline.

Repair connection.
Windows could not finish repairing the connection because the following actions cannot be completed
Renewing the IP address

Running cmd-> netsh diag gui
Results:
Network adapters [00000011] Intel (R) PRO/1000 MT Mobile Connection FAILED
->DefaultIPGateway = 64.139.239.196 (Different Subnet)(FAILED)


and running ipconfig /release, then ipconfig /renew I get this error after a long timeout.
An Error occurred while renewing interface Local Area Connection : Unable to contact your DHCP server. Request has timed out.


When I restart the laptop, and I check on Network Connection Details, I see an IP address of 169.254.117.205 (I know that a 169 address is significant in some way....but I don't know what to do about it) Subnet mask is 255.255.0.0


I'm baffled by what's causing this, and I don't quite know what to even google search for.

Also, if there's something else that would be good to know, let me know....I'm currently studying computer engineering at the university and can probably provide any extra information that you might need to help me fix this issue.

[Chevy]

Originally Posted by Demosai

The Pathline
Cable from the wall goes to a Motorola cable modem
The ethernet cable from the modem goes to a Linksys 10/100 Workgroup switch port 1

And here's the problem.

Your ISP (like most) is only going to allow one connection. It happens to be that your desktop got their first.

If you replace the 10/100 switch with a router, then you can use multiple machines (your ISP will see the router as the one allowed connection, and will have no knowledge of what is behind it).

You would go from the Cable Modem to the WAN/Internet Port on the router, then use one of the LAN ports for the desktop, etc.

[Demosai]

Originally Posted by Chevy

And here's the problem.

Your ISP (like most) is only going to allow one connection. It happens to be that your desktop got their first.

If you replace the 10/100 switch with a router, then you can use multiple machines (your ISP will see the router as the one allowed connection, and will have no knowledge of what is behind it).

You would go from the Cable Modem to the WAN/Internet Port on the router, then use one of the LAN ports for the desktop, etc.

that would explain why it worked behind a wireless router a few weeks ago for a mini-LAN party but not behind a switch...

so if i reset everything and then just connect my laptop, it should work...well, I'll try that out and report back on it.


(the war against my ISP continues XD )

[johnwill]

Don't you just love the easy ones Chevy?