How to use Microsoft PowerShell and PsExec to change the RDS license server name on all your XenApp servers
You're not going to RDP into hundreds of XenApp servers to change the RDS license server name. Use PowerShell and PsExec to update the registry key on all of them at once.

Let's say you decide to decommission your Remote Desktop Services (RDS)/Terminal Services Licensing Server or you moved your TS/RDS CALs to a different server. That means you need to change the name to the new server under Remote Desktop Session Host Configuration on all your XenApp servers.
This is a pain to do manually when you have several hundred XenApp servers. You can do it through group policy but you may only want to change it on a subset of servers in an OU and not all of them. So I used PowerShell and PsExec to precisely target all my XenApp servers I wanted to change. It's a very quick option when you are pressed for time.
You'll need to create rds.bat and rds.ps1 and put them in "d:\rdsscript" on the server you plan to run the Powershell script from. You'll want to share out your "d:\rdsscript" folder on the server you plan on running the script from, otherwise you might get Access Denied errors because the script references a UNC path. The contents of these two files is below.
rds.bat contents:
powershell.exe -executionPolicy unrestricted -command "\\yourserver\rdsscript\rds.ps1"
rds.ps1 contents:
Import-Module RemoteDesktopServices
cd RDS:\
cd .\RDSConfiguration\LicensingSettings\SpecifiedLicenseServers
new-item –name newlicenseserver.yourdomain.fqdn
remove-item oldlicenseserver.yourdomain.fqdn -confirm:$false -recurse:$true
Modify the rds.ps1 script with the name(s) of the servers you want to add a the name(s) of the servers you want to remove. You can run rds.bat locally on a XenApp server as a test to see if it worked.
Now it's time to run it on all your XenApp servers remotely. You can use any number of delivery methods. Again I chose to use PsExec because it's quick and gets the job done. I highly recommend doing your dev, staging, etc. servers first before doing it in production.
Now copy PsExec.exe into the "d:\rdsscript" folder. You'll also want to create psexec.bat and xenappserverlist.txt now. Here are the contents of the two files:
psexec.bat contents:
psexec -s @xenappserverlist.txt "\\yourserver\rdsscript\rds.bat"
pause
xenappserverlist.txt contents:
XenAppServer01
XenAppServer02
XenAppServer03
XenAppServer04
XenAppServer05
So your shared directory on the server you plan on running the script from will look something like this:

Now just double click on psexec.bat and it will run the script on each of your XenApp servers in the list. The "-s" tells psexec to execute as the local system account so you don't have to put your username and password in the script. I don't like to put usernames and passwords in the script because doing that would send it across the network in plain text so it may be a security concern.
Hope this helps. Let me know if you have any other methods to accomplish an RDS license server migration quickly. I'm always looking for more options. :)

Jason Samuel
Product leader, advisor, and international speaker with 27+ years in enterprise end-user computing, security, and cloud. Has deployed infrastructure at Fortune 500 scale across 34 countries. 1 of 3 people globally to hold Citrix CTP + VMware vExpert + VMware EUC Champion concurrently. 200+ articles, 1,000+ reader discussions.
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