This article provides steps to resolve the following error when adding discovered scopes overlapping with existing subnets:
X scopes has not been added because it is overlapping with existing subnet!
All IPAM versions
1. Ensure that the scope is expanded or contracted both ways or in one direction.
2. Modify either the start or the endip address one at a time and immediately applying the changes after each and every change to the start or end ip address of the scope.
3. If two stand-alone DHCP servers are servicing the same subnet, ensure that you are not overlapping the available pool on each DHCP server as they do NOT share the DHCP database and are not aware of the leases that are assigned. By excluding addresses, you ensure that IPs will not be offered that may otherwise be in use.