topic Hi Mark, in Switching

IP DHCP Conflict in Catalyst 4500

ferly0001 — Fri, 08 Mar 2019 18:51:53 GMT

Dear all,

I have a problem of dhcp conflict on my core switch cisco 4500 E.

Everyday i have found some of my IPPhone device get lost ip address, when i check in core that is so many ip dhcp conflict, so i type command clear ip dhcp conflict, after that my IPPhone can get IP address again. So everyday i should type that command. My range IP address is /23 and my IPPhone only 325 units.

Could you please give me the solution about this issue ? i attached the capture about the log and ios version

Thanks for your help

Hi,

johnd2310 — Tue, 06 Jun 2017 06:18:51 GMT

Hi,

What is the lease period of your pool? Have you tried a smaller lease period?

Thanks

John

Hi

Mark Malone — Tue, 06 Jun 2017 09:18:04 GMT

follow this guide it should help

http://blog.ipspace.net/2007/08/dhcp-conflict-logging-true-story.html

Hi Mark,

ferly0001 — Fri, 09 Jun 2017 01:48:44 GMT

Hi Mark,

Thanks for your comment, i will try from guide that suggestion at weekend

Hi Johnd2310,

The lease period is default 1 day, i didn't try to make smaller lease period. Do you have any recommended lease period ?

Hold on, this chassis is

Leo Laohoo — Fri, 09 Jun 2017 03:03:51 GMT

Hold on, this chassis is running on 3.3.0E????

I'd upgrade the firmware first.

Hi Leo,

ferly0001 — Fri, 09 Jun 2017 03:28:18 GMT

Hi Leo,

running on 03.03.00.SG

3.6.6 would be a more stable

Mark Malone — Fri, 09 Jun 2017 07:17:47 GMT

3.6.6 would be a more stable version than 3.3 , some of the earlier version had a lot of bugs , that release is 2012