Creating exclusion ranges prevents the DHCP server from assigning a client lease with any address in the exclusion range, thereby protecting it for use as a static IP address.
Reservations, however, are used to create a permanent IP address lease assignment by the DHCP server.
Although reservations can still be created using IP addresses within an exclusion range, this may cause issues.
IPAM is the administration of DNS and DHCP, while DHCP is actually not responsible for IP addresses in the exclusion range. I suppose that's why the Servers defined in the excluded range are not assigned to the network in IPAM.
If you would like the servers to have their specific IP addresses, there is no need to create an exclusion range. You may try deleting the range from the address pool and let reservations do the job.
For your reference:
Hope this resolves your Query !!
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