Currently we have one DHCP server which is on a 2003R2 Domain. the address range is 192.168.1.x with a subnet mask of 255.255.240   .  I am trying to create a second scope with  addresses from  192.168.9.1 - 192.168.9.254  , i have set the subnet to 255.255.240 and i get an error about address range and mask conflict with an existing scope. I am not the best at network as you can probably tell , how could i solve this? 

The aim of the second scope is to set a class ID so all our VOIP phones can get a different default gateway address than our normal clients. 

 Thanks in advance 

Hi,

Thank you for your post.

Yes, the range and mask setting caused the conflict.

1. If you use 192.168.1.1 with subnet mask 255.255.240.0.
The ip range is from 192.168.1.1 to 192.168.15.254.
Since your second scope only need ip number 254, your second scope should use 192.168.16.1 to 192.168.16.254 with subnet mask 255.255.255.0.

2. If you would like use 192.168.9.1 to 192.168.9.254.
First, change the first scope subnet mask to 255.255.248.0, the ip range is from 192.168.1.1 to 192.168.7.254.
Then, set second scope 192.168.9.1 to 192.168.9.254 with subnet mask 255.255.255.0.

If there are more inquiries on this issue, please feel free to let us know.

Regards,
Rick Tan
Forum Support
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I've got a similar problem, but I can't see why I should have such a range/subnet mask conflict.

I've already got a DHCP address pool of 10.0.0.160 to 10.0.0.240 with /8 subnet mask.

When I try to add a second scope of 10.0.0.60 to 10.0.0.100 with /8 subnet mask I get

the same error. My understanding is that my first address pool consists of the contiguous

addresses 10.0.0.60, 10.0.0.61, 10.0.0.62, ..., 10.0.0.97, 10.0.0.98, 10.0.0.99 and finally

10.0.0.100.

So why should there be a conflict?

Regards

Jorgos