2008 R2 DHCP server no longer authorized

Today I noticed that one of our DHCP servers was no longer Authorized.  

Here is what is in Event Viewer.

The DHCP service failed to see a directory server for authorization.What would cause this?

How do I fix this?
J.R. SitmanIT DirectorAsked:
Who is Participating?

Improve company productivity with a Business Account.Sign Up

x
 
MaheshConnect With a Mentor ArchitectCommented:
If after reboot still its not working try to follow instructions in below article
http://djadwinsvr.blogspot.in/2013/04/managing-dhcp-servers-active-directory.html#!/2013/04/managing-dhcp-servers-active-directory.html

still you do not get success, then note down all DHCP scope information including Scope options, server options, exclusions, reservations and uninstall DHCP server role from server, remove any entries of problematic dhcp server from adsiedit.msc if found as my earlier comment,
reboot the server, install DHCP server role and reconfigure the dhcp scopes.
try to authorize DHCP server at this time should work

Mahesh
0
 
Peter HutchisonSenior Network Systems SpecialistCommented:
Make sure that the DNS entries are correct and they can lookup Directory servers.
Make sure no firewall is enabled that may block access to Directory services.
Make sure the the DHCP server is joined to the domain and computer account is available and enabled.
0
 
J.R. SitmanIT DirectorAuthor Commented:
DNS entries are ok.  I can ping the other servers in the Domain.
There is no firewall
DHCP server is a DC and I can access it with no problem.
0
Problems using Powershell and Active Directory?

Managing Active Directory does not always have to be complicated.  If you are spending more time trying instead of doing, then it's time to look at something else. For nearly 20 years, AD admins around the world have used one tool for day-to-day AD management: Hyena. Discover why

 
J.R. SitmanIT DirectorAuthor Commented:
When I tried to authorize the server I got "The specified servers are already present in the directory service"
0
 
MaheshArchitectCommented:
Try below.
1.Start Active Directory Sites and Services on PDC
2.Click Services, and then click Net Services. If you cannot see Services, click to select Show Services Node on the View menu.
3.In the right pane, right-click the name of the DHCP servers that you cannot add to Active Directory, and then click Delete.
4.When the Are you sure you want to delete this object? message appears, click Yes.
5.Force replication of Active Directory to the other sites
6.Start Adsiedit.msc with Configuration partition.
7.Expand to CN=Configuration, CN=Services, and then click CN=NetServices.
8.Right-click CN=Your_DHCP_Root, and then click Properties.
9.In the Select a property to view list, click DHCPServers.
10.In the Values list, click the name of the new DHCP server, click Remove, and then click OK.
11.Click CN=NetServices, right-click the entry for the new DHCP server, and then click Delete.
13.Force replication of Active Directory to the other sites
14 Run ipconfig /flushdns and dnscmd /clearcache on PDC
14.Restart the DHCP Server.
15.Authorize the DHCP servers again.
Note - You must be member of Enterprise admins group in order to authorize the server

Reference articles
http://support.microsoft.com/kb/306925 - written for 2000 server, but applicable to later versions also
http://bloke.org/windows/active-directory-dhcp-authorisation-issues/

Mahesh
0
 
J.R. SitmanIT DirectorAuthor Commented:
I'm stuck at #7.  See attached
adsiedit.png
0
 
J.R. SitmanIT DirectorAuthor Commented:
OK, I've made it to #10.  In the Values list the problem server is not listed.  See attachment.
adsi2.png
0
 
MaheshArchitectCommented:
You have opened wrong partition
Close this connection and Open configuration partition through adsiedit.msc

Mahesh
0
 
MaheshArchitectCommented:
In the step 8, go to properties of cn=dhcproot and check if it works
0
 
J.R. SitmanIT DirectorAuthor Commented:
I'm confused.  It shows "Configuration[SPCALA185.LASPCA.LOCAL].  See attached.
adsi3.png
0
 
MaheshArchitectCommented:
Are you started adsiedit.msc on PDC server ?
What is the name of PDC server ?
What is the name of DHCP server having problem ?

Mahesh
0
 
J.R. SitmanIT DirectorAuthor Commented:
yes I'm on PDC.  PDC and DHCP server are the same.  I also have a second DHCP server with a different Address pool.
0
 
MaheshArchitectCommented:
Ok
In the step 8, go to properties of cn=dhcproot
In the Select a property to view list, click DHCPServers
In the Values list, click the name of the new DHCP server (PDC), click Remove, and then click OK.
Force replication of Active Directory to the other sites
Run ipconfig /flushdns and dnscmd /clearcache on PDC
Reboot the DHCP Server (PDC)
Authorize the DHCP servers again.
Note - You must be member of Enterprise admins group in order to authorize the server
0
 
J.R. SitmanIT DirectorAuthor Commented:
These is no "Select a property to view"    See attached.

Can you send a screen shot?
adsi4.png
0
 
MaheshArchitectCommented:
In properties of cn=dhcproot,
are you able to find "DHCPServers" if yes go to its properties

Mahesh
0
 
J.R. SitmanIT DirectorAuthor Commented:
yes and the only servers listed there are two that were removed years ago.
0
 
J.R. SitmanIT DirectorAuthor Commented:
I deleted the old DHCP servers and ran the command lines.
0
 
MaheshArchitectCommented:
Can you please force AD replication, restart DHCP service and then try to authorize the same
Login on server with account having enterprise and domain admins right

let me know the results please

Mahesh
0
 
J.R. SitmanIT DirectorAuthor Commented:
I'm still getting this.  However, the server is rebooting now.
dhcp1.png
0
 
J.R. SitmanIT DirectorAuthor Commented:
I followed the steps in your last post/article.  Unfortunately I didn't know it was going to remove all the settings.  My fault.  I think I can recreate the scope.  However, The server is hung up.  I'll be there Tuesday and post them.

Thanks for hanging in to help.
0
 
J.R. SitmanIT DirectorAuthor Commented:
I was able to force a reboot on the problem DHCP server.  The link to the article you sent fixed it.  Also I thought all my DHCP setting were gone, but they weren't.

Thanks for all the help.
0
 
J.R. SitmanIT DirectorAuthor Commented:
The article in this post fixed the problem.

Thanks
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.