Also, to add to this... if you have a WINS server with a corrupt database, that could be adding to the confusion for Duplicate IPs. I've had this happen to me before, and didn't realize it until I decided to just look at the WINS server to see what it thought was true of the LAN topology. It's just something to keep in mind.
Mark -----Original Message----- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]] On Behalf Of Brian Hill Sent: Wednesday, May 22, 2002 6:01 AM To: [EMAIL PROTECTED] Subject: RE: DHCP NACK problems [7:44671] Is it always NACKing for the same IP lease? Normally, the DHCP process works like this: The client sends a DHCPDISCOVER to find a DHCP server, the server responds with a DHCPOFFER, offering the client an IP, the client responds with a DHCPREQUEST to choose the IP address (in case it gets an offer for more than 1), and the server responds with a DHCPACK, sealing the deal. However, MS DHCP servers have a "feature" that allows them to detect IP address conflicts before responding with an ACK. What I would check is a few things: First, if this is happening due to a conflict detection, you should see under active leases in DHCP a "BAD ADDRESS" listed by the IP. If you see that, ping the IP in question. If you get a response, track down the PC, and do an ipconfig to find it's DHCP server. Then track down that server and kill it :) Hope this helps, Brian Hill CCNP, CCDP, MCSE 2000 (Charter Member),MCSE+I (NT4.0), MCSA (Charter Member), MCP+I, MCP(21), Inet+, Net+, A+ Lead Technology Architect, TechTrain Author: Cisco, The Complete Reference http://www.alfageek.com Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=44717&t=44671 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]