Creating Subnets

To create a subnet, complete the following:

1. In the Infoblox Portal, click Configure > Networking > IPAM/DHCP > Address Spaces > Create -> Subnet > IPv4 Subnet or IPv6 Subnet.

2. On the Create Subnet page, specify the following:
   

   • Address: Enter an address for the subnet and specify the netmask. Universal DDI  supports /32 prefix network for IPv4 and /128 prefixed networks for IPv6. However, you cannot create a range or a fixed address for /32 and /128 networks. You cannot assign a NIOS-X Server to /32 or /128 subnets. You can create a reserved IP for /32 and /128 networks.

   • Get next available: Select the check box to allow Universal DDI to automatically get the next available subnet. Once you select the check box, you do not need to specify the IP address. However, you must specify the CIDR. This field is available only if the parent address block exists. For more information, see Configuring Next Available Network. This is not applicable to IPv6.
   • Quantity: Specify an integer between 1-20. This is not applicable to IPv6.

   • Name: Enter a name for the subnet.

   • Description: Enter additional information about the subnet.

   • IP Space: Select an IP space from the IP Space column selector to associate the subnet with it. You can also create a new IP space by selecting New and specifying Name and Description for the IP space.

   • Service Instance: Choose a service instance or HA Group from the column selector. Alternatively, you can choose Use Parent NIOS-X Server.

   • Federated Realms: Choose the Federated Realm and move it from Available to Selected by clicking >>. A delegation is created in the Federated Realm for the subnet. For more information, see Federated Realms. 
   • Disable for DHCP Protocol: Select the check box to stop the DHCP server from offering addresses in this subnet. 

   • Tags: For information about tags, see Managing Tags.
     

   • Configure the following components of DHCP Configuration:
     • Automated Scope Management: The values are inherited from the Global DHCP Configuration. You can override and specify a different value. For more information, see Configuring Automated Scope Management. This is not applicable to IPv6.
     • Leases: The values are inherited from the Global DHCP Configuration. You can override and specify a different value. For more information, see Defining Lease Times.
     • DHCP Options: The values are inherited from the Global DHCP Configuration by default. For more information on configuring DHCP options in Global DHCP Configuration, see Configuring DHCP Options. You can configure the inheritance for each item granularly. For more information, see Granular Inheritance of DHCP Options.

     • DDNS: DDNS updates go to Universal DDI-managed zones or zones hosted by an external DNS server. For example, you can configure NIOS as the external primary server. The Default DDNS Domain Name is inherited from the zones defined in the Global DHCP Properties or DHCP Config Profile. See Enabling DDNS for IPv4 Clients. You can override the settings and specify a different value for the Default DDNS Domain Name. 

       Note

       If you override the DDNS settings, specify a Default DDNS Domain Name that is valid with respect to the DDNS Zones configuration in the Global DHCP Properties or DHCP Config profile for DDNS updates to be successful.

     • Filters: The values are inherited from the Global DHCP Configuration. You can override and specify a different value. For more information, see Configuring DHCP Filters.

3. Click Save & Close to save the details or click Cancel to exit.