Constant DHCPREQUEST and DHCPACK between devices and server

Simon Hobson dhcp1 at
Thu Sep 13 11:59:31 UTC 2012

<Campbell.ColinD at> wrote:

>I just upgraded a box from RHEL5.8 (DHCP3.0.5) to RHEL6.3 (DHCP 4.1.1).
>The leases file was copied from what used to be the server's partner
>(it's still running RHEL5.8).
>I now get a constant stream (multiples per second) of
>DHCPREQUEST/DHCPACK between the devices still active on the network.
>Anyone know what is happening and how to fix it?

Did you try looking in the archives ?
Is the server on the same address, and does it have the same config, 
as the old one ?

The usual advice is that  either the response isn't making it back to 
the client, or it is in some way not acceptable to the client.

Use a packet sniffer to see that responses are actually making it 
back to the client's network, and if possible check on the client to 
see that it is receiving it.
Look in the logs on the client to see if it's seeing the responses 
and/or if it's logging any errors.
It may be worth forcing a client to explicitly release it's lease and 
see if it works better when doing the full Discover-Ack-Request-Offer 

Simon Hobson

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author Gladys Hobson. Novels - poetry - short stories - ideal as
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