By default when a lease is first issued to a client, it adheres to the Maximum Client Lead Time (MCLT) value, not the value on the DHCP scope. This is considered a temporary lease period given by a failover server to a new client. In addition to providing a temporary lease to client, it specifies the amount of time for which a DHCP lease may be renewed by either failover peer without contacting the other. It also specifies the amount of time that either DHCP server will wait in a “partner down” state before assuming control of the entire IP address range within the scope. ( default = 1 hour ).
Maximum Client Lead Time (MCLT) can be found when configuring DHCP failover in the following location in the setup wizard.
- Windows Server 2012 DHCP Failover, an initial lease always = the MCLT (Maximum Client Lead Time)
- Afterwards the same client will renew and get whatever is defined in the scope definition.