I found an acceptable answer to my own question on http://www.tek-tips.com/faqs.cfm?fid=1925: "How it Works for Non-Windows Clients: Because non-Windows clients do not contain a registry, an alternative solution was developed: When a non-Windows client connects to a MetaFrame session for the first time, the target MetaFrame server to which they connect requests a TS CAL from the license server. Then, instead of passing the TS CAL to the non-Windows client, the CAL is stored in that MetaFrame server's registry, beneath HKEY_LOCAL_MACHINE\SOFTWARE\Citrix\MSLicensing\. Whenever the non-Windows client returns to that MetaFrame server, no license request is necessary because the license already exists in that MetaFrame server's registry. If the same non-Windows client then connects to a second MetaFrame server in the same domain, the second MetaFrame server requests a CAL from the license server as before. However, because the license server has already issued a CAL for that client, the same CAL is re-issued to the second MetaFrame server. This scenario assumes that all MetaFrame servers share a single common Terminal Services Licensing server. In both cases, the non-Windows ICA Client is not reached by the Terminal Services License server directly. The target MetaFrame server requests a TS CAL from the license server on the client's behalf and then retains a copy of the TS CAL for future use. Over time, all MetaFrame servers in a load-balanced farm will contain copies of the TS CALs for all non-Windows clients." Thanks, James _____ From: thin-bounce@xxxxxxxxxxxxx [mailto:thin-bounce@xxxxxxxxxxxxx] On Behalf Of James Masters Sent: Monday, October 31, 2005 10:19 AM To: thin@xxxxxxxxxxxxx Subject: [THIN] Linux client licensing Hello, all. How is licensing handled with Linux ICA clients? Is something written to the local file system, or is something stored in the registry on the MetaFrame server? (We're on MF XP FR3, win2k3) Thanks, James