In the DHCP server module dhcpsrv.c, two of the service functions are empty. Shouldn't there be some processing in there? For example, DHCPSRV_service_release should place the IP address back in the pool.
You are right, upon receipt of a DHCPRELEASE message, the server marks the network address as not allocated and retain a record of the client's initialization parameters for possible reuse. Upon receipt of a DHCPDECLINE message, the server must mark the network address as not available and should notify the local system adminstrator of a possible configuration problem.
unfortunately, these two functions are not implemented yet, and no plan to implement it in classic MQX 4.x yet. I would suggest you implement it by yourself if it is necessary.
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