Can I change the CIDR of an existing network?

CIDR changes are restricted when IP reservations exist or if the new CIDR isn't a valid subset.

It is typically more practical to establish a fresh network with the appropriate CIDR parameters from the outset. This approach avoids the limitations and complications associated with modifying existing network configurations that may have dependencies or reservation constraints. The CIDR calculator can help you size the new block and its subnets first.