You need a trace closer to the client. Most likely the offer is not making it to the client or request is not making it back to the server.
Possible causes - 1. packetloss at client side 2. rouge dhcp server On 12/13/2016 02:23 PM, Atanas P Atanasov wrote: > We’re a seeing some odd behavior in our wireless deployment, seemingly random > clients aren’t able to obtain an IP via DHCP > > When analyzing the DHCP logs and also debugs on the wireless controller, we > see the clients sending a DHCP DISCOVER > packet and the DHCP server responds with a DHCP OFFER. However the client > doesn’t follow up with a DHCP REQUEST. This > behavior continues sometimes for hours, until the client finally sends a DHCP > REQUEST and obtains a lease. > > The side effect of this is our DHCP servers are getting long delays when the > dhcp service is restarted. We are using > Infoblox dhcp severs in a failover group. From a support case we have opened > with Infoblox, they have determined that > these excessive dhcp requests are increasing the number of dhcp leases in the > database which causes the long restart. > > We have seen similar behavior with our wired clients but in lot smaller > numbers. > > > > We’re a Cisco shop, using 8450 controllers, code version is 8.2.121 > > > > Attached is a Splunk search on one of the “misbehaving” clients’ MAC > > Any comments are appreciated. > > > > Atanas Atanasov > > Network Engineer > > Syracuse University > > > > ********** Participation and subscription information for this EDUCAUSE > Constituent Group discussion list can be found > at http://www.educause.edu/groups/. > ********** Participation and subscription information for this EDUCAUSE Constituent Group discussion list can be found at http://www.educause.edu/groups/.
