First of all, there is a potential risk involved in cut-over migration from LCS 2005 to Lync 2013 and it is not supported by Microsoft.
Purpose of this blog is to understand the direct migration path from LCS 2005 to Lync 2013 RTM and reveal the challenges. I have successfully deployed a standard LCS 2005 server. Few test users were created on AD and enabled them for LCS and successfully tested client connectivity and sign-in.
Lync 2013 Schema update and Topology deployment
As it was a non-tested scenario, I was bit doubtful about Lync 2013 schema update on existing LCS Active directory forest. However, decided to test the impact and consequences. I went through Lync 2013 schema update successfully. Fortunately , I didn’t faced any error during the update. I have included below figure for the reference;
I went ahead with Lync server 2013 topology and published succssfully. A standard edition server has been implemented successfully. Lync 2013 standard edition pool name is Lync2013-rtm.seattle.com. Here is the Topology summary;
I have created few more users on AD specifically for Lync 2013 co-existance testing. Successfully enabled users for Lync 2013. Also, using LDAP search LCS users were visible on Lync control panel with Legacy tag. Here is the legacy user information for the reference;
Co-existance - Admin portals and clients
I have successfully enabled few Lync 2013 users on existing LCS 2005 environment. Tested admin portal access on same time from two different VM part of same AD forest. I was able to connect Lync control panel and LCS anagement console. Lync frontend and LCS servers were rebooted several times for testing,but all came back as expected. You should be able to see the admin portals on below figure;
Client interoperability was another major area to be tested. I have logged in from two different client machines using LCS and Lync 2013 clients. I didn’t experienced any challenges during client deployment except, you can’t publish multiple SRV records on sip domain. Hence , I had to use manual configuration on Lync 2013 client for sign-in.
LCS 2005 - Cut over user migration
The whole idea was to delete the users from LCS and enable them for Lync 2013. I wanted to make sure that user contacts were backed up prior to the migration. I have used DBIMPEXP tool to back up the contact from LCS.
Once user contacts were exported, I have disabled that user from LCS management console. Here is the screenshot attached for the reference.
You should be able to see the disabled users on the console , select those users and delete them permently.
You should be able to see the staus once activity has been completed. Currently, user was successfully deleted from LCS.
User enablement - Lync server 2013
The moment I deleted that user from LCS , I was able to see the same AD user on Lync control panel without legacy tag. I have highlighted same on below figure.
I was all set for user enablement on Lync -2013 control panel. Went user enablement wizard and created Lync user instantly.
LCS 2005 contact migration to Lync 2013
Contact migration from LCS to Lync 2013 was the major challenge. DMIMPEXP tool has been replaced with Import-CSuserdata cmdlet in Lync 2013. Ideally , DBIMPEXP output would be an XML file, but Lync 2013 cmdlet accept
compressed zip file as input. There is another cmdlet available to convert the legacy files to compressed zip (convert-csuserdata) file. But , unfortunately it did not work for me.
Below figure , I tried with legacy XML input for contact import , but it gave me an error. I tried with Legacyformat cmdlet and it failed to convert the file.
For testing , I tried to export contact from OCS-R2 platform and tested convert-csuserdata cmdlet. It was accepting the input and shown user wasn't available error. This is just to confirm that the cmdlet was not able to convert the LCS XML file.
Then , I tried with DBIMPEXP and it does not allow me to open the RTC database. My account has enough permission to modify everything on AD and standard editon database.
Finally , I have decided to mannually add the contacts to Lync 2012 client. Good news is , I was able to sign-in to client without any issues.
Cut over migration isn't a recommended topology by Microsoft and it is an unsupported configuration. It's your choice if you want to go with this approch. I hope , this article would be helpful for reference.