
There are two different types of migration methods from Legacy to Modern DHCP(Kea):
When switching from ISC DHCP to Kea DHCP, the corresponding ISC DHCP services should be stopped and disabled for both IPv4 and IPv6.
DHCPv4:
systemctl stop dhcpd
systemctl disable dhcpd
DHCPv6:
systemctl stop dhcpd6
systemctl disable dhcpd6
This ensures that the ISC DHCPv4 and DHCPv6 services are stopped and do not automatically start after switching to Kea DHCP.

