Can't find DHCP server

[stduc]

I'm just throwing this on here for opinions.

This morning - my SO's PC would not connect to our network. To summarise

1. Cold boot failed

2. Repair of network connection failed

3. Fixing the IP address - worked!

Now - I would have said - OK - reboot the router. HOWEVER I tested the physical connection by removing it from her PC and plugging it into a laptop - and got an IP address.

I know I need to reboot the router - which I will do - however - has anyone seen this before? Could this be an early sign of issues with her PC's onboard NIC?

BTW - The laptop and my PC all got assigned an IP address just fine.

 

[edfair]

Over the years I've seen several routers that have been picky in handing out addresses to various PCs on the lan they control.

In every case the server would respond to a ping but never to a DHCP request. I also have been known to put another router in place to verify that the problem was with the router or combination. Nothing further has ever shown up as a problem with the network stuff on the PC and they have worked fine when manually assigning IP address.

One particular router started with 1 PC and over 3 years has failed on increasing numbers until I am now manually assigned on every machine connected to it.

One side benefit is the ability to lock things down via firewall.

Ed Fair
Give the wrong symptoms, get the wrong solutions.

 

[VinceWhirlwind]

Apparently, either the PC wasn't sending a DHCP request, or, the router wasn't answering it.

As the router answered the laptop's DHCP request, it was likely working fine - check the router log to see if it was specifically unhappy with the PC's request.

With the amount of security software on PCs these days, some of it actually replaces the IP stack, it's more likely a software issue on the PC.

Best way to know for sure what was happening is to install Wireshark on network and sniff all traffic on the router interface. I doubt the router interface can be configured to port mirror (check) so you might need to add a managed switch to your network which you can configure to mirror the PC or router port.

 

[stduc]

A router reboot fixed it. I'm rapidly going off netgear routers.