I have setup a failover DHCP server configuration in Hot standby mode between two Windows 2012 R2 servers in the same subnet. The Max Client Lead Time is 5 minutes and the State Switchover Interval is 15 minutes. The addresses reserved for standby is 0% because we don't have enough addresses.
When I stop de DHCP server on the primary server after 15 minutes the hot standby server switches the scope over to partner down and 5 minutes later it's serving out IP-addresses. Only now comes the problem / fun part. The stand-by server is leasing out correct ip-addresses from the scope, but it does it with the 5 minutes lease time as configured in the MCLT. He does this for the entire time the Primary server is down. So every 5 minutes it leases the same ip-adres to the client for an other 5 minutes. over and over again.
Is this normal behavior? I thought that after 15 minutes of switchover interval plus the 5 minutes of MCLT it takes over the complete scope and acts like it's the primary server.