Quarantine VLAN/DHCP range not updating DNS

[CyberDrac]

We have a mechanism by which all of our wired and wireless machines authenticate against AD via 802.1x in order to be allocated an IP range appropriate to its location, anything that fails this authentication will be assigned an IP address in the Quarantine VLAN and the associated DHCP Range with access to a limited number of machines required for rebuilds and the like.

 

Therefore any machine that is powering on will briefly go through a stage where they are allocated a quarantine address, only for it to be replaced a few seconds later with a valid IP from the range for the location in which the switch resides.

 

The behaviour we are observing is that the DNS entry for a machine is retaining the Quarantine VLAN address not the address it ultimately ends up using. As you can imagine this causes some issues.

 

Has anyone got any thoughts on what might be happening, I have tried a number of things including the reduction of lease times and scavenging to ensure that the address come back into circulation again and get re-assigned the correct IP with limited success.