# Creating and Managing a User-defined Network

#### Create a User-defined Network

1. Log in to the management console.
2. Under Computing, click Bare Metal Server.

   The BMS console is displayed.

3. Click the User-defined Networks tab and click Create User-defined Network.
4. Set Name, VPC, AZ, VLAN, and User-defined Subnet.
   - User-defined Subnet: The subnet mask ranges from 16 to 29. The gateway IP address of the user-defined subnet cannot be one used by any other tenant. In addition, the CIDR of the user-defined subnet cannot conflict with that of the VPC subnet.
   - The VLAN ranges from 1 to 4094. User-defined subnets of the same user-defined network must have different VLANs.
5. Click OK.

   After the user-defined network is created, you can view its status, VPC, and subnets in the list of user-defined networks.

   If you have not created a multi-NIC BMS, message "Insufficient multi-NIC BMSs." is displayed and the user-defined network fails to be created.

#### Change the Name of a User-defined Network

1. On the BMS console, click the User-defined Networks tab. Locate the row that contains the target user-defined network and click Modify in the Operation column.
2. Enter a new name and click OK.

#### View Details About a User-defined Network

1. On the BMS console, click the User-defined Networks tab.
2. In the list of user-defined networks, click the name of the target user-defined network.

   You can view the name, AZ, number of user-defined subnets, and VPC information of the user-defined network.

   You can also change the name of the user-defined network by clicking next to its name, entering a new name, and then clicking .

#### Manage a User-defined Subnet

- Add a user-defined subnet.

  On the page showing details of the user-defined network, click Add User-defined Subnet. In the displayed dialog box, enter an IP address, set the VLAN, and click OK.

- View details about a user-defined subnet.

  In the list of user-defined subnets, click the name of the target user-defined subnet to go to its details page.

  On the IP Addresses page, you can view the IP address of the user-defined subnet and the EIP bound to the subnet.

  On the BMSs page, you can view information about all the BMSs with multiple NICs.

- Modify a user-defined subnet.

  You cannot directly modify a user-defined subnet. You must delete the user-defined network and then create a new user-defined network and a user-defined subnet again.

- Delete a user-defined subnet.

  In the list of user-defined subnets, locate the target user-defined subnet and click Delete in the Operation column.

  If a user-defined network has only one subnet, you are not allowed to delete the subnet.

#### Delete a User-defined Network

1. On the BMS console, click the User-defined Networks tab.
2. Locate the target user-defined network, click Delete in the Operation column, and click OK in the displayed dialog box.

   After the last multi-NIC BMS using a user-defined network is deleted, the user-defined network will be unavailable and needs to be deleted manually. To use user-defined networks later, you must create new ones.

Parent topic: User-defined Network