If you are sniffing on the client or at the switch, Wireshark. If you are sniffing on the server, either Wireshark or the Network Monitoring Tools that come with the OS.
However, if you can get one of these machines to get an IP address, and then do an 'ipconfig /all' you'll see what it thinks is the DHCP server. Kurt On Wed, Feb 17, 2010 at 06:46, John Hornbuckle <john.hornbuc...@taylor.k12.fl.us> wrote: > Yesterday I started having some DHCP weirdness that has grown today. I’m > kind of stumped and need some guidance. > > > > DHCP server is Windows Server 2008. It’s also a DC and DNS server. It shows > no errors relating to DHCP in Event Viewer, and there are plenty of > addresses left in the scope. It can be pinged from client machines at >1 ms > and no timeouts, and it can ping client machines with the same results. DNS > is working fine. DC functions are working fine. > > > > DHCP, unfortunately, appears spotty. A number of clients (although > apparently not all, from what I can tell) can’t get leases. If you run > ipconfig /renew from a command prompt, they report that they can’t contact > the DHCP server. If you manually assign an IP address, all works fine. So > network connectivity seems okay—this seems to be strictly a DHCP issue. > > > > I’m guessing that I’m going to need a packet sniffer to further > troubleshoot. I have to confess, though, that I’ve never in my life used > one. I’ve just never needed to. > > > > So, can anyone recommend a free, simple packet sniffer I can run from a > client machine to watch the DHCP traffic? And what, exactly, should I be > looking for? > > > > > > > > John Hornbuckle > > MIS Department > > Taylor County School District > > www.taylor.k12.fl.us > > > > > > > > > > NOTICE: Florida has a broad public records law. Most written communications > to or from this entity are public records that will be disclosed to the > public and the media upon request. E-mail communications may be subject to > public disclosure. > ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~
