From ISC Dhcp user

[Simon Hobson]

Vladislav A Kulikov wrote:

>>>range 10.10.10.1;
>>>allow members of "blah-blah-blah";


>Problem is not here.
>When we change MAC on PC - server answers: no free leases
>So problem not in switch. =(

It will do, that is known and expected behavior
You have one address, it is leased to a specific device, if another 
device comes along, there is no free lease to give it.
There is no easy way round this - I think.

IIRC there was talk of making the database primary key 
admin-definable - so you'd be able to change it to circuit-id. But I 
think it's never made it into code - I think ISC would be happy is 
someone wanted to sponsor it ;-)

-- 
Simon Hobson

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