When requesting an IP already allocated, a DHCPNAK should be returned

Chaigneau, Nicolas nicolas.chaigneau at capgemini.com
Fri Sep 19 13:46:33 UTC 2014


Here is another use case which does not strictly abides to RFCs:

When a client sends a Request with a specific IP address which is already leased to someone else, Kea sends back an "Ack" with another (available) IP address.

According to RFC2131, a DHCPNAK should be returned in this case:

    If the selected server is unable to satisfy the DHCPREQUEST message
     (e.g., the requested network address has been allocated), the
     server SHOULD respond with a DHCPNAK message.

This is somehow similar to the issue described in:


This message contains information that may be privileged or confidential and is the property of the Capgemini Group. It is intended only for the person to whom it is addressed. If you are not the intended recipient, you are not authorized to read, print, retain, copy, disseminate, distribute, or use this message or any part thereof. If you receive this message in error, please notify the sender immediately and delete all copies of this message.

More information about the kea-dev mailing list