helpfor option ping-check

[Steven Carr]

There is no quick fix for this really, you need to identify each issue
and then diagnose and remedy.

There is possibly a fix but it needs to be implemented on the network
side of things. If all of your clients are meant to be using DHCP then
most modern managed switches have a feature called "DHCP Snooping"
which will only allow the client to connect to the network if it sees
DHCP address allocation take place. This way it will prevent anyone
from manually configuring an IP address on their machine.



On 30 June 2013 01:12, Julie Xu <J.Xu at uws.edu.au> wrote:
> Great thanks, Simon.
>
> It really rescues me from hopeless.
>
> Next problem is how do I fix it?
>
> Can I protect this case on configuration of dhcpd.conf? Or something has to be done on window site?
>
> Please advice
>
> Julie Xu
>
> On 28/06/2013, at 9:42 PM, "Simon Hobson" <dhcp1 at thehobsons.co.uk> wrote:
>
>> Julie Xu wrote:
>>> The problem is between two machines who are in dynamic pool, no of them in reserved area.
>>
>> As already stated, this should not normally happen. However one thing that will cause it is if two devices have the same Client ID set - that signals to the server that they are the same client regardless of having different MACs etc.
>>
>> That should be obvious from the lease file entries - the Client IDs will be shown.
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