A common theme I am seeing lately is that people have setup Lync test environments, and are required to start from scratch for one reason or another. The problem is active directory is still detecting their old topology and causing issues with moving forward with the new environment.This post will cover what is required to remove references to the Lync deployment from Active Directory.
One very important thing to note here, once you extend your AD Schema, unless you revert from a backup, you will not be able to back out those changes. As a quick reference, lets go over what Lync Server 2010 does when you extend the schema.
In Office Communications Server 2007 R2, majority of configuration data was stored in Active Directory, however Lync Server 2010 stores most of the configuration data in the Central Management Store, which is a SQL database that lives on your servers in the topology. Lync Server 2010 still stores certain information in active directory including:
- Schema extensions:
- User object extensions
- Extensions for Office Communications Server 2007 and Office Communications Server 2007 R2 classes to maintain backwards compatibility with supported previous versions
- Data (stored in Lync Server extended schema and in existing schema classes):
- User SIP Uniform Resource Identifier (URI) and other user settings
- Contact objects for applications such as Response Group and Conferencing Attendant
- A pointer to the Central Management store
- Kerberos Authentication Account (an optional computer object)
Now, there are a ton of Attributes and Classes involved, because of the backwards compatibility with OCS 2007 R2, however I am simply going to cover the references to your pools, pool servers and your topology, and how to get rid of them. When the RTM documentation is released, it will have a full list of all attributes and classes.
Central Management Store References
The key change in Lync Server 2010 is the reference to the Central Management Store that is created in active directory. When you install your first server in the environment an Active Directory Service Connection Point is created in AD referencing the location of the central management store, all servers going forward pull from that reference point to identify where they should be pulling configuration data from. Once they have made that first pull, Lync Server 2010 keeps each of the local configuration stores up to date in a replication process. It’s a similar setup to Active Directory, if you think about domain controllers having a local store of data, and it replicates across all, same concept with the Lync CMS.
You can view this SCP through ADSI Edit.
Open ADSI Edit and connect to the context where your data is stored, either Configuration or System. Below I am showing System.
Expand Microsoft->RTC Service->Topology Settings
If your right click and choose Properties you will see the most important data, the server and version that is holding the CMS.
Essentially the commands below manage this entry.
There are a couple PowerShell commands that can be used to manage the CMS Connection in Active Directory.
Commands to view the status and location of the CMS
The command Get-CSManagementStoreReplicationStatus
This command can be run by itself to see the status of replication across all of the servers in your topology
You can also run this command with the switch –CentralManagementStoreStatus to view information about your central management store:
This command will give you very valuable information, for this purpose it will show you what your connection point is referencing, and in troubleshooting, you will be able to identify any issues with your CMS.
You can also do a very basic command to report on the location of the CMS.
The command Get-CSConfigurationStoreLocation
This simple command will print the CMS location in a single line.
There are a couple ways we can change where the CMS reference in AD points to, as well as to completely remove the connection point.
Modifying or Deleting the CMS Location in Active Directory
The command Move-CSManagementServer
This command will move your CMS between pools. This is useful if you have your existing CMS still online, and will be making a smooth transition to the new servers. If you do not have your old CMS server available, you will not be able to use this command unless you have a valid backup of your configuration data. These backups can be obtained by running Export-CSConfiguration and Export-CSLISConfiguration. That will backup to ZIP files, which can then be used with the Move-CSManagement store command to restore the configuration and repoint the SCP to the new pool.
The syntax for this command is pretty basic, here is the reference from the Help File:
Before you move the Central Management Server, you must do the following:
1. Verify that you have created the new Central Management store. This is d
one by running the Install-CsDatabase cmdlet and using the CentralManagemen
2. If you are moving the Central Management Server to a Standard Edition se
rver, verify that you have used local setup to run the Prepare Standard Edi
tion server option. This advance preparation is required to add firewall ru
les that will allow Windows PowerShell to remotely access the new Central M
3. Verify that there is enough free disk space on the computer where Move-C
sManagementStore is being run to accommodate the Central Management Server.
4. Verify that the Front End Server service has been installed on the compu
ter where Move-CsManagementStore is being run. If this service is not insta
lled, and running, then the move will fail.
5. Verify that you can successfully run the Enable-CsTopology cmdlet on the
computer where Move-CsManagementStore is going to be run. If Enable-CsTopo
logy cannot be run on that computer then the move will fail and you will no
longer have a functioning Central Management store.
After you have completed these steps, all you need to do to move the Centra
l Management Server from Pool A to Pool B is log on to a computer in Pool B
and then call Move-CsManagementServer without any additional parameters:
When you do that, Move-CsManagementServer will consult the topology to dete
rmine the prior location of the Central Management Server (Pool A), and th
en transfer the Central Management Server and the Central Management store
to the current pool (Pool B).
If the move succeeds, Move-CsManagementServer will display a list of comput
ers on the screen. In order to finish the move, you must run local setup on
each of these computers. Computers in Pool A will still be running an inac
tive version of the Central Management service; running local setup will de
lete that service. The computer in Pool B where the Central Management Serv
er was moved will be running the Central Management service; however, other
computers in the pool will not. Running local setup on these computers wil
l install the Central Management service.
Two important parts:
- Make sure you have properly prepared your new Front End/Pool Server prior to running this command (see documentation on setting that up)
- Login to the NEW server which will contain the CMS, open the Lync Powershell, and run Move-CSManagementServer
The command Remove-CSConfigurationStoreLocation
This command will actually remove the service control point in Active Directory that points to your Central Management Store. You can also include the parameter –Report with a file path to output a report of the activity for confirmation.
When you perform Remove-CSconfigurationStoreLocation the reference is deleted from active directory.
This step would be more common in lab scenarios where you are starting from scratch and just need a quick and dirty way to remove reference to your topology. To completely remove references to old topology objects, you will also need to remove some additional entries using ADSI Edit.
How to Remove Server Entries from AD using ADSI Edit
When you deploy a Lync topology in your environment, the servers are also references in AD. Most importantly, when you do not properly remove a server, there will be stale references to this throughout the entire RTC Service CN in Active Directory.
I will show you how to remove references to these old servers and old pools.
When you are looking at the tree, you will find specific references to servers and pools in Global Settings, Pools, Trusted MCUs, Trusted Services and Trusted WebComponentsServers.
You may also find old references to application contacts and conference directories if those were not properly removed. It is safe to say that you can run through each of these and remove references to your old servers if you are certain they will not be in use anymore.
Global Settings and Trusted Services
If you expand Global Settings you will see entries, the number of entries will depend on how much you have going on in your environment.
We can search for specific servers are are looking to remove by using LDP to perform queries looking for this server.
First, you must open LDP and bind to the correct DN.
Start->Run type LDP and hit enter
Select Connection choose Connect and enter a valid domain controller to connect to
Then you must Bind as a valid user, choose Connection and choose Bind, either use the currently logged in user, or specify an account with privileges.
Now we will display the Tree we will be searching through. Select View->Tree
If your information is stored in your System container, you must choose DC=domain,DC=com where domain is your domain. If it is stored in configuration you should choose CN=Configuration,DC=Domain,DC=COM
Expand down to your RTC Service container that we were viewing before in ADSI Edit
Now that we are bound and connected to the correct tree, its time to start searching. If your server is referenced in Global Settings or Trusted Services we will be looking for msRTCSIP-TrustedServerFQDN
Right Click on RTC Service and choose Search
For the filter enter the following, replacing serverfqdn with the server you wish to remove
In my example I am searching for “winx-cs2010b3.winxnet.com”
Make sure to select Subtree so it searches all trees below for this entry.
Select Run, the query should return results in the right pane with specific CNs, we will want to navigate to these Cs and delete them.
Copy these results, we will use them as a reference to delete these entries using ADSI edit.
Before deleting, review the properties of each of the CN to make sure it is a valid item to delete. Most of these are references to the individual services on those machines, which is evident from the different TrustedServicePort and ServiceType
Open ADSI Edit for each entry in your search results, navigate to the full DN, right click and choose Delete
Pools usually does not require the use of LDP as the list is so short and easy to identify. Lync identifies pools in active directory with numbers, if you have any beta pools, you may also see them referenced as Sitename:1,2,3 . As you can see in my screenshot, I have a few of each. identify the pool you want to delete, and simply right click and choose Delete
The Trusted MCUs entry is similar to Trusted Services. We will perform a LDP query for the attribute msRTCSIP-TrustedMCUFQDN
Follow the steps above for Global Settings and Trusted Services replacing msRTCSIP-TrustedServerFQDN with msRTCSIP-TrustedMCUFQDN
Your results should return three per server, because of IM/Audio/Video and Data. Copy the results and set aside.
Following the same steps above for Global Settings and Trusted Services, delete each DN that you wish to remove.
Trusted WebComponentsServers entries are created usually per front end server you put in your environment both for OCS 2007 R2 and Lync Server 2010. You can search using LDP and the attribute msRTCSIP-TrustedWebComponentsServerFQDN
Follow the same steps above to search for that attribute, and delete any DNs associated with the server you are trying to remove.
I hope this helps people understand how the central management store is referenced in active directory, and also how to do some cleanup if you did not properly remove servers from your environment. As always. open to comments about ways to improve the methods, or your own methods for performing these steps!