How to configure DHCP failover cluster between two Linux Servers

[dhcp1 (primary)]---[dhcp2(secondary)]

Install dhcp service on both servers
Configure as the following:

1#Master dhcp server: 192.168.200.10
#vim /etc/dhcpd.conf
failover peer "dhcp" {
         primary;
         address 192.168.200.10;          # local host IP address
         port 647;                      # make sure this port is not used by other programs
         peer address 192.168.200.20;     # backup host IP address
         peer port 647;
         max-response-delay 60;
         max-unacked-updates 10;
         mclt 600;
         split 128;
         load balance max seconds 3;
      }

      subnet 192.168.200.0 netmask 255.255.255.0 {
        pool {
          failover peer "dhcp";
          range 192.168.200.100 192.168.200.200;
          deny dynamic bootp clients;
        }
        option routers 192.168.200.2;
      }

2#Slave dhcp server: 192.168.200.20
#vim /etc/dhcpd.conf
failover peer "dhcp" {
         secondary;
         address 192.168.200.20;         # local host IP address
         port 647;                     # make sure this port is not used by other
                                         programs
         peer address 192.168.200.10;    # primary host IP address
         peer port 647;
         max-response-delay 60;
         max-unacked-updates 10;

      subnet 192.168.200.0 netmask 255.255.255.0 {
     
        pool {
          failover peer "dhcp";
          range 192.168.200.100 192.168.200.200;
          deny dynamic bootp clients;
        }
        option routers 192.168.200.2;
      }