6.10 Checking a DHCP Server

To monitor DHCP services, the plugin check_dhcp is available. It sends a DHCPDISCOVER via UDP broadcast to the target port 67 and waits for an offer from a DHCP server in the form of a DHCPOFFER, which offers an IP address and further configuration information.

Because check_dhcp does not send a DHCPREQUEST after this, the server does not need to reserve the sources and to confirm this reservation with DHCPACK, nor does it need to reject the request with DHCPNACK.

Granting the plugin root permissions

Granting the plugin root permissions

There is a further restriction to the check_dhcp: it requires full access to the network interface and must therefore run with root privileges.

In order for the user nagios to be able to ...

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