how do i remove DHCP scope from server 2012r2 failover when on server is missing the scope

2017-01-18

Question

_{Wednesday, January 18, 2017 1:16 PM}

I have two 2012r2 dhcp servers with about 50 or so dhcp scopes. servers are currently using failover between the two servers in "hot standby" mode. one of the scopes was deleted from replication partner and now when I try to deconfigure failover relationship, it fails with the error "Deconfigure failover failed: Error: 20005. The specified subnet does not exist.

when I try removing via powershell using the command

Remove-DhcpServerv4Scope -ScopeId x.x.x.x -ComputerName <computerservername> -force

I get the error

Remove-DhcpServerv4Scope : Failed to delete scope 10.188.172.0 on DHCP server BFMVNETDNY1.
At line:1 char:1

Remove-DhcpServerv4Scope -ScopeId 10.188.172.0 -ComputerName BFMVNETD ...

+ CategoryInfo : ResourceExists: (10.188.172.0:root/Microsoft/...cpServerv4Scope) [Remove-DhcpServerv4Scope], CimException
+ FullyQualifiedErrorId : DHCP 20113,Remove-DhcpServerv4Scope

Is there a way to remove this without breaking replication for the rest of my scopes?

All replies (3)

_{Thursday, January 19, 2017 5:40 AM}

Hi Knowlton,

>>when I try to deconfigure failover relationship, it fails with the error "Deconfigure failover failed: Error: 20005. The specified subnet does not exist.

Did you mean that you remove failover relationship from DHCP servers?

Have you checked if client could obtain IP address from this scope?

Have you tried to add this scope in DHCP server to check if this scope exists?

To delete failover relation ship, please check link below to understand it:

DHCP Failover Relationships

https://technet.microsoft.com/en-us/library/dn338986(v=ws.11).aspx

Best Regards

John

Please remember to mark the replies as answers if they help.
If you have feedback for TechNet Subscriber Support, contact [email protected].

_{Thursday, January 19, 2017 5:47 AM}

Did you mean that you remove failover relationship from DHCP servers? relationship for that scope was "manually" removed from server "B", but is still active on Server "A". Server "A" thinks the replication partner is still there, but the scope is not there. when i try to remove partner relationship for that scope, I get an error. if I try to remove the scope from server "A"(with or without -force switch), I get the error in my original post

Have you checked if client could obtain IP address from this scope? yes

Have you tried to add this scope in DHCP server to check if this scope exists? it's still an active scope on server "A".

_{Friday, January 20, 2017 9:52 AM}

Hi Knowlton,

>>when i try to remove partner relationship for that scope, I get an error

Please try to restart DHCP server and check again.

Since this issue is complicate on this forum, I suggest you open a case with Microsoft, more in-depth investigation can be done so that you would get a more satisfying explanation and solution to this issue.
Here is the link:
https://support.microsoft.com/en-us/gp/support-options-for-business