DHCP Scope in Use 100%

Hi all,
I have DHCP server High Availability running on Windows Server 2012 R2.
Today, one of my DHCP scope is 100% in use.
But when i total IP leases and IP reservation on that scope from DHCP GUI, total hostname that get IP is less than 460.
When i get IP address usage on that scope using command get-dhcpserverv4lease -scope id 10.1.12.0 -alllease, there is +- 460 hostname that get IP address from that scope.
I found that some hostname is BADADDRESS or the DHCP session is expired, i try to remove that hostname from IP leases, but it didn't work. (Remove-dhcpserverv4lease -ipaddress x.x.x.x)
When i check from DHCP GUI, that scope always 100% in use and Computer cannot get IP Address from that DHCP scope again.
Can you help me resolve this issue?
Thanks before!
Best Regards,
Henry Stefanus

Hi Henry,
>>I found that some hostname is BADADDRESS or the DHCP session is expired
BADADDRESS means that the IP address is used by other computer. Please check if any computer has configured static IP address.
>>Can you help me resolve this issue?
Use scope extension to expand the address range for the current scope.
Reduce the lease duration and decrease the cleanup interval. This can help to speed the reclaiming of expired scope IP addresses.
For detailed information, please refer to the link below:
https://technet.microsoft.com/en-us/library/dd380166(v=ws.10).aspx
Best Regards.
Steven Lee Please remember to mark the replies as answers if they help and unmark them if they provide no help. If you have feedback for TechNet Support, contact [email protected]

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