I have two questions with regard to the DHCP server functionality offered in ROS.
Is it possible to configure two DHCP servers on seperate RB’s with identical information, so they load balance when both are online, or still provide DHCP services when one is offline? Fall-back DHCP?
Is it possible to assign a fixed IP address to a client based on his MAC address from the DHCP server?
But what about leases database? If one server fail than secondary server needs to know what address is assigned to what and when it expires?
Maybe it could be done by some periodic synchronization by SSH from other server but DHCP servers should have some cluster support for automatic synchronization.
No, the secondary server doesn’t need to know. The client will attempt to renew its lease with the primary and fail to do so, and upon failure do a new broadcast for a new DHCP server. If you want to completely rule out duplicate IP addresses on the network use different pools on the two servers.