DHCP server config on 1841

[jforst]

This does not work:

>>>>>>>>>>>

no ip dhcp conflict logging

!

ip dhcp pool dhcp1

network 10.1.10.32 255.255.255.240

default-router 10.1.10.101

>>>>>>>>>

with an debug ip dhcp server events message that 10.1.10.101 does not have a pool (.101 is the FA0/0 ip addr with /24 mask)

This does:

no ip dhcp conflict logging

ip dhcp excluded-address 10.1.10.0 10.1.10.32

ip dhcp excluded-address 10.1.10.63 10.1.10.255

!

ip dhcp pool dhcp1

network 10.1.10.0 255.255.255.0

default-router 10.1.10.101

!

Why does the first not work? I would think that limiting the network using /28 should work fine, without the need for the exclude statements.

Help?

TIA,

Jason

[sstudsdahl]

Jason,

The first example that you list fails because the network that you've defined for the DHCP pool is 10.1.10.32/28. The IP address of the interface you want DHCP to function on must fall within the network that you define in your DHCP pool. Since the 10.1.10.32/28 includes addresses 10.1.10.32 through 10.1.10.47, the IP of Fa0/0 (10.1.10.101) falls outside this range and as a result, will not be associated to the DHCP pool. With this in mind, if you were to assign IP addresses from the 10.1.10.32/28 pool to users off of the FA0/0 interface, they would not be able to reach the default gateway since it would fall on a different subnet according to the netmask that you would be passing out with the DHCP server.

HTH

Steve

[jforst]

Steve said: "...10.1.10.32/28 pool to users off of the FA0/0 interface, they would not be able to reach the default gateway since it would fall on a different subnet ..."

DOH!!!! Now, why did that not occur to me? I think I was distracted by the 'exclude' addresses. I was thinking that the /28 would just serve the addresses from 33-62, not remembering, apparently, that the mask is also served. But that brings up: If you want to serve a range from an interface, do you have to exclude addresses on either side? There is no way to define the _range_ to serve without the exclude statements?

Thanks Steve.

Jason

[thisisshanky]

I dont think there is a way to specify a range of addresses, without excluding the rest.

[jforst]

Thanks guys.

Would be nice if the command was something like:

<<<<

ip dhcp pool poolname

int fa0/0

ip address a.b.c.d mask

ip dhcp poolname

>>>>>

eliminates the exclude commands, it would seem to me.

thanks for the information guys.

Jason