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From the Infoblox Portal, click Manage Configure > Networking > IPAM/DHCP > Address Spaces.
Click IP Space > Address Block > corresponding > corresponding Subnet > select the Address Range link.
On the Address Range page, click the Create drop-down list > Reservation> Reservation.
On the Create Reservation page, specify the following:
IP Space: Refers to a fixed address.
Range: The respective address range is automatically selected. A range can also be created under a subnet.
IP Address: Enter an IP address to be used as the reservation.
Name: Enter a name for the reservation (recommended).
Description: Enter additional information about the reservation (optional).
Tags: For information about tags, see Using Tags.
Click Save & Close to save the fixed address, or click Cancel to exit.