DHCP MAC blocking in a dynamic range
An Infoblox administrator (email firstname.lastname@example.org) can configure the ability for an infoblox user to populate a list of MAC addresses that will be denied an address in a DHCP dynamic range.
Once this is configured, the form for adding MAC addresses will be found under:
Data Management -> DHCP -> IPv4 Filters
Select the appropriate filter list.
You will need to supply a MAC address; there is an optional space for a comment.