Decreasing The DHCP Scope

Question

I have a Windows 2012 Domain. I want to reduce my DHCP scope.

1) Can I lower the ending IP address without affecting/disconnecting clients that currently have one of the IPs that I am removing from the scope?

2) Can I add (or still keep my existing) reservations that are outside the newly reduced scope range?

Thread source link: https://social.technet.microsoft.com/Forums/en-US/9f282bd5-2a26-4e97-82ae-28b6927a11a6/decreasing-the-dhcp-scope?forum=winserverNIS

Answer 1

Hi ,

Welcome to our new Microsoft Q&A Platform.

1.Based on my experience, reducing your DHCP scope will not affect your clients, even though their IP addresses are out of scope. When DHCP clients restart or it’s time to renew lease, they’ll send request message to renew IP address lease. Then they will be denied and request a new IP address during scope range. You can refer to the following link:

https://serverfault.com/questions/751618/how-to-change-ip-address-pool-in-dhcp-scope-without-affecting-existing-leased-ip

2.As long as reserved addresses are not assigned to other clients, you can keep your existing reservations. Please refer to the following link:

https://serverfault.com/questions/716836/windows-dhcp-reservation-outside-of-lease-pool

Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.

https://social.technet.microsoft.com/Forums/en-US/7e95374c-c77c-411d-989f-a540d7248ccf/dhcp-reservations-falling-outside-of-scope-they-are-reserved-in?forum=winserveripamdhcpdns

Best Regards,

Candy