Document how to create a new Windows VM for Bazel's CI
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+# Creating a new Windows VM image for Bazel's CI
+
+The key thing to keep in mind is that the Windows setup for Jenkins has nothing magic about it
+that makes it a Jenkins slave VM. It's just a normal Windows setup with a few pre-installed tools
+that you would install on a workstation anyway. The Jenkins-specific setup is then handled
+completely automatic by the PowerShell script in `gce/jenkins-slave-windows-2016.ps1`.
+
+## Necessary steps
+- Create a new GCE VM with Windows Server 2016.
+- Temporarily enable RDP access to the VM via:
+ - `gcloud compute firewall-rules create $USER-rdp --allow=tcp:3389,udp:3389 --source-ranges=$(curl v4.ifconfig.co)/32`
+- Set a new Windows password, note it somewhere and connect via RDP.
+
+- Server Manager -> Configure this local server
+ - Deactivate Windows Firewall.
+ - Deactivate Windows Defender.
+ - Deactivate IE Enhanced Security Configuration.
+ - Set time zone to Europe/Berlin.
+
+- Download and install Google Chrome. Pin to taskbar, unpin IE.
+
+- Settings -> Update & security
+ - For developers -> [x] Developer mode. Click all three "Apply" buttons below.
+ - Windows Update -> Advanced options -> Check "Give me updates for other Microsoft products".
+ - Windows Update -> Check updates, then install all updates.
+ - Reboot if necessary.
+ - Repeat until no more updates are found.
+
+- Go to https://www.python.org/downloads/windows/
+ - Download latest stable Python 3.x (64-Bit).
+ - Start installation.
+ - Check "Install launcher for all users".
+ - Check "Add Python to PATH".
+ - Customize installation, check all boxes.
+ - Check "Install for all users".
+ - Customize install location: C:\Python3
+ - When setup is complete, click "Disable path length limit", then close setup.
+
+- Go to http://www.msys2.org/
+ - Download latest x86_64 msys2 setup.
+ - Install to C:\msys64.
+ - Launch msys2 shell from installer, run "pacman -Syuu", forcibly close terminal window when prompted.
+ - Launch "MSYS2 MinGW 64-bit" shell, run "pacman -Syuu", install all updates.
+ - Run "pacman -S git curl zip unzip gcc zlib-devel isl tar patch".
+
+- Go to http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html
+ - Download and install latest "Windows x64" JDK 8.
+
+- Go to http://landinghub.visualstudio.com/visual-cpp-build-tools
+ - Download "Visual C++ Build Tools 2015".
+ - Start installation, choose "Custom", select all options, install.
+
+- Go to https://nssm.cc/download
+ - Download "nssm 2.24-101-g897c7ad (2017-04-26)" or later build.
+ - Create new folder: "C:\Program Files\nssm".
+ - Extract nssm.exe from the download ZIP file's "win64" folder into the just created folder.
+
+- Start -> Search for "path" -> Choose "Edit the system environment variables"
+ - Click "Environment Variables". Do the following actions in the lower "System variables" part of the UI.
+ - Add "C:\Program Files\nssm" to the PATH variable.
+ - Set BAZEL_VC to "C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC"
+ - Set BAZEL_SH to "C:\msys64\usr\bin\bash.exe"
+ - Set JAVA_HOME to "C:\Program Files\Java\jdk1.8.0_152" (or the latest version installed)
+
+- Start -> Type "GCESysprep", run it.
+ - The system will shut down and prepare itself for being used as an image to create new VMs.
