Home Network Problems...

[The Duck]

I have a linksys WRT54G router at home. It is less then a year old. I have 2 computers connected to it, one wired and one wirelessly. All of a sudden the wired computer can't get to the internet. This is my mother's computer and it's a mess. So I just save what she needs and reinstall the OS via the recovery CD's (the PC is an HP pavilion). So after that process I set it to automatically recieve an IP from the router. However it's not communicating with the router at all... I can't ping the router or anything. I checked the routers DCHP IP table and interestingly enough the router sees the computer, says it's assaigned an IP and it shows the PC's mac. So I doubt it's the cat5 or NIC causing the problems. And to confirm this I connected the PC directly to the modem and it works...

After doing this I decide to manually set the IP with the default subnet (255.255.255.0) and it still cannot communicate with the router. I also switched the port which the cat5 connects to on the router. Keep in mind this PC was able to connect to the internet through the router before... I'm pretty stumped... Any suggestions? It has to be something with the router but all of the settings check out... At this point I'm guessing that the router ports have gone faulty... which is pretty weird...

[Ghost_25inf]

well run a ping on the localmachine. ping 192.168.1.100 if thats the ip of the computer or ping localhost. then see if the cable is bad. reverse the cable and see if that helps some time the cable comes loose from the back of the computer or the router. What is your ip anyways? use the other computer to see if the cable is fine and the ports on the router. Update the drivers for the nic.

If you cant ping the local host = Bad NIC
if you cant connect using the other computer = bad cable
If updates for the nic doesnt help = see other two possibilies

You can also update the firmware on the router if need be.
Most likely its a bad cable.

[The Duck]

I don't think it's a bad cable because I used it to hook up the PC directly to the modem and it worked... Which also rules out a bad NIC?

I'll try updating the firmware, but my other PC that's connected wirelessly is working fine...

The IP of the PC is 192.168.1.104, at least that's what the DCHP table says it was assaigned...

Pinging the router from the PC or the PC from the router results in 100% packet loss ...

Weird thing is the DCHP table shows the PC and Mac and the assaigned IP... I even changed the name of the PC and it shows the name change...

I'll also see if updating the NIC drivers will help... But it was working fine for almost a year up until a couple of days ago...

[HTRegz]

Hey Hey,

*shakes his head at parts of this thread and gets down to business*

Ghost_25inf: Pinging localhost and the IP Addres assigned to the NIC interface are two different things... localhost = 127.0.0.1 = loopback = seperate interface handled in software... a way of testing your network stack... no response from localhost is definately _NOT_ indicitive of a bad NIC... it demonstrates a problem with the Network Stack on the OS (commonly reset with netsh interface ip reset reset.log or by deleting TCP/IP from your networking (both windows fixes))

Duck: If you run ipconfig on the PC is an IP Address listed for the interface? the DHCP Table of the router says it's assigned an address but does the PC itself indicate an actual address?

If it works direct to the modem (I'm assuming you checkd your ip address and it was valid and that you could route traffic to various public websites)... Then you have an odd problem going on..

If ipconfig doesn't reveal an actual IP Address run ipconfig /release and ipconfig /renew, however run Ethereal while doing it... ensure that the proper DHCP request is occuring..

DHCP Discover, DHCP Offer, DHCP Request, DHCP Ack...

If you see a Discover than your PC is sending a request..
If you see an Offer than the Routers DHCP Server is offering back an address
Request means that the PC is accepting that address and asking for permission to use it
Ack Means go ahead and use it

If you see all of that and you still don't have connectivity then provide the following here

ipconfig /all results
route print results
arp -a results

Peace,
HT