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From the Infoblox Portal, click Manage Configure > Networking > IPAM/DHCP > DHCP Config Profiles. The list of DHCP Subnet Profiles is displayed.
Click ☰ > Edit or select the respective record and click the Edit button to modify a DHCP Subnet Profile.
In the Subnets section, click Add. Choose the IP space, click the subnet, and click Select. Repeat the step to add additional subnets.
Click Save & Close to save the record or click Cancel to cancel.