I am requested to install a Linux- Dhcp server in our network for some subnets. After setting up everything, I ran into the following problem. It seems that Webmin does not recognise the service-start during the boot-sequence of ubuntu. If you click start in webmin-panel you start a second process of isc-dhcpd-service.
Reasons for that is a false webmin module-config, which comes with default parameter for an old configuration.
To solve that, you need to modify the module-config to the following parameter.
Change the highlighted fields to this:
Command to start DHCP server:
service isc-dhcp-server start
Command to stop DHCP server:
service isc-dhcp-server stop
Command to apply configuration:
service isc-dhcp-server restart
Path to DHCP server PID file:
Click save. After that everything works for me as expected.