Requested in thread http://forum.univention.de/viewtopic.php?f=11&t=3571 So as I understand, the user wants for UCS a preconfigured shadow copy VFS module and the posibility to activate the shadow copy for shared folders by UMC module Shares and/or configuration by UCR variables.
also requested by customer Ticket#2015112321000495 for Citrix-Offline-Client
The server filesystem needs to support this. According to https://web.archive.org/web/20170905182943/https://wiki.linuxhotel.de/doku.php/admin_grundlagen:shadow_copy LVM or hardlinks could be used serverside.
This issue has been filled against UCS 4.0. The maintenance with bug and security fixes for UCS 4.0 has ended on 31st of May 2016. Customers still on UCS 4.0 are encouraged to update to UCS 4.3. Please contact your partner or Univention for any questions. If this issue still occurs in newer UCS versions, please use "Clone this bug" or simply reopen the issue. In this case please provide detailed information on how this issue is affecting you.