In Windows Server 2016 Technical Preview 4 we introduced a new installer: Windows Server App (WSA). WSA is important as it is the officially supported Server Installer going forward and is the only installer available on Nano Server. WSA is a significant shift from the traditional MSI installer technology (for more background read the blog posted in TP4). In particular, WSA has no Custom Actions which means that it is purely declarative. In a recent interview, our Technical Fellow Jeffrey Snover called MSI Actions “the portal to hell” for servers. WSA’s declarative architecture enables us to meet the demanding needs of server scenarios.
To increase reliability of an application’s uninstall and upgrade, we have added support for several new APPX extensions in Technical Preview 5 (TP5). These extensions replace the old MSI way of using custom actions for creating performance counters and ETW providers, making them first class citizens that are handled by the WSA installer. Below is the current extension support:
- NT Service – released in TP4
- WMI provider – released in TP4
- COM classes/Interfaces/AppIDs – released in TP4. However, the COM extension is subject to further breaking changes for Windows Server 2016 RTM and beyond.
- Performance counter – new in TP5
- ETW provider – new in TP5
In addition to Nano Server, WSA is now also available for the Server with Full Desktop Experience SKU. This enables server applications to use a single, uniform WSA package regardless of which Windows Server installation option was used.
Try it out! Let us know your feedback.