Subnetting Error

[grundy]

Trying to configure a new firewall. Exisiting ip for trusted interface is 10.0.0.x/8 (255.0.0.0). I want to setup the DMZ as 10.0.1.x but no matter what subnet i try it says it's overlapping?

Whats the best way to setup the dmz without changing the subnet of all the hosts on the trusted?

Any ideas?

 

[PalmTest]

Hi grundy,

You stated: "Exisiting ip for trusted interface is 10.0.0.x/8 (255.0.0.0)".
This means that the DMZ subnet 10.0.x.x always fits inside this /8 subnet, regardles of the DMZ subnet you use.
If you do not want to change the /8 on the trusted interface, then you must use an other IP range for the DMZ, because the 10.x.x.x subnet is completely used by the Trusted interface.

 

[minxca]

use 172.16-31.x.x or 192.168.x.x for your dmz

 

[cyberspace]

as winito suggests.

Systems Administrator
BSc Network Computing, CCNA. Both in training!