How to configure DHCP Server on Cisco IOS

Lessons Discussion
41

Hello Sebastian

What the documentation is saying is that the IP address on the router interface is already excluded from any DHCP scope that is being used. For example, looking at the topology from the lesson:

image
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Let’s say that the DHCP server is configured with the following:

interface FastEthernet0/0
 ip address 192.168.12.254 255.255.255.0
!
ip dhcp pool MYPOOL
 network 192.168.12.0 255.255.255.0
 default-router 192.168.12.254
 dns-server 208.67.222.222
!
end

Note that one of the interfaces of the DHCP server, namely Fa0/0, is assigned an IP address within that scope. What the Cisco documentation is saying is that there is an implicit exclude command like so:

ip dhcp excluded-address 192.168.12.254

So the IP address of the interface which is within the scope of the DHCP pool is automatically excluded without needing to add any additional configurations.

This is true regardless of whether or not that particular IP address is the gateway of the scope.

I hope this has been helpful!

Laz