DHCP Server - Running, but not issuing

[Borvik]

Ok, we are running our DHCP server on Win2k3 server (unable to update, and all it does is DHCP and internal DNS).

We had a power outage yesterday, the server is up and running - but apparently not dishing out IP addresses. The DHCP Server service is "Started" (I have restarted the service _and_ the server itself multiple times).

Computers seems to be running (don't know how they are all DHCP, must be on a previous lease), but I don't know for how long. A /release /renew fails to pull obtain an IP address saying it couldn't contact the DHCP server.

Our printers are on DHCP (reserved IPs to keep them static) and failed to get IP addresses - I have switched them over to manually assigned so we can print.

I am able to ping the DHCP server, and the DHCP server can also ping out to Google.

The fact that there are multiple devices affected (5 printers, and at least 2 computers - don't want to risk testing more and taking them completely offline) make it seems like there should be a common point of failure, most likely the server - but I'm uncertain of what to do next?

Anyone have any ideas?

 

[Borvik]

Ok, so DHCP service _is_ technically functional - but still not handing out IP addresses.

This was confirmed by running a DHCP test client:

http://blog.thecybershadow.net/2013/01/10/dhcp-test-client/

Running this on the server resulted in a success, on client machines failures. It would appear that something in the network is stopping this from running properly. I'll be rebooting our switches after hours.

 

[Borvik]

After having two different professionals look at this, we have a working DHCP server again - but it wasn't really fixed.

Prof1: Looked at server and tried a few different things with no result - concluded that the problem was in our network stack and we should reboot our switches. Prof1 didn't have the knowledge to delve into that area further.

We tried rebooting the switches after hours, with no results and began talks with Prof2.

I disconnected the DHCP server and hooked it and a laptop up to an old dumb HUB we had to eliminate any network config issues. Still nothing. Prof1's idea of the network stack just fell through.

Notified Prof2 of everything tried, and Prof2 remoted in and looked at our server - concluded it FUBARed and migrated the DHCP services to our other DC. DHCP is now working, but we still have no idea what was going on - though we are working on replacing our server.

 

[GlenJohnson]

What did the logs show? You said you restarted the dhcp service. Did you stop it, reboot, then try and restart it? Just a thought. Good luck.

Be civil to all; sociable to many; familiar with few; friend to one; enemy to none.
Benjamin Franklin

 

[Borvik]

Interesting thought to reboot the system with the service stopped (and presumably disabled so it could be manually started and reenabled).

The professionals both did look at the logs, but I'm not certain what they saw.

It's moot now though, the service is running on another system - and I've got the authorization to order some new servers to make these modern 2012 r2!