What is clientID(DHCP Server in ROS)?
It creates client station itself? And then it forwards the DHCP server?
What is an example of use?
When a users machine makes a DHCP request it can optionally include an id. Typically this is something like a known host name, but IIRC it can be arbitrary. The DHCP server can then use this id to identify the machine and assign an address to it.
When configuring static leases under “/ip dhcp-server lease” the expected client-id can be specified. If it is then the clients DHCP requests must include the matching id.
/ip dhcp-server lease
add address=10.0.1.200 server=default client-id="termax"
add address=10.0.1.201 mac-address=00:00:00:00:00:00 server=default client-id="termax2"
In the first example any DHCP request with client id of “termax” will match and be assigned 10.0.1.200, in the second example both the MAC address and the client id in the request must match.
Without static assignments, the displayed client-id for a dynamic lease assignment is the one (if any) that was sent with the request.