slow dhcp on 1G backbone.

[Blake Hudson]

-------- Original Message  --------
Subject: Re: slow dhcp on 1G backbone.
From: Dean Montgomery <dmonty at sd73.bc.ca>
To: Users of ISC DHCP <dhcp-users at lists.isc.org>
Date: Friday, July 24, 2009 2:33:09 PM
> I've attached a wireshark capture on: udp port 68 and port 67
> as well as syslog dhcp entries.
>
> You will see 2 requests:
> 1) Once from bios for pxeboot.
> 2) Once from the kernel has loaded.
>
>
>
> ===
>
> I tried turning off spanning tree on the switches.  It still takes 12 or more seconds from the time the diskless client starts looking for an IP to the time that it actually gets one that it can work with.
>
> ===
>
> Windows machines are also affected by slow dhcp requests:
>  ipconfig /release 
>  ipconfig /renew
>   .... wait .... wait ...  wait ...
>
> ===
> Another note - wake on lan is turned on on all the clients so the nic and switch link lights are always on.
>
>   
Where are these 12 second delays in your capture/syslog? Are the clients 
sending requests that are not seen by the server?

--Blake