You can add new networking elements in MAAS such as fabrics, VLANs, subnets, and spaces. MAAS should detect new network elements automatically. Otherwise, you can add them manually.
To add a new subnet:
In the MAAS web UI, open the Subnets page.
Select Subnet in the Add drop-down menu at the top-right corner.
Specify Name, CIDR, Gateway IP, DNS servers, Fabric & VLAN, and Space.
Click Add subnet.
See also