Setting HostName for DNS

Is it possible to set the DNS HostName so that other applications can find the IP address? This is required if using dynamic DHCP addresses.
Additionally, does Dns.GetHostEntry support returning the HostName for a provided IP address? The HostName appears to always return null.
Thank you.
(using TinyCLR 2.1.0 Preview 3.)

As I know, currently doesn’t support provided IP to name.