Doc - Upgrade on Windows (#7682)

Documentation/Books/Manual/Installation/Windows.md

@@ -74,7 +74,7 @@ avoids the data being synced to the windows domain controller.
 
 If this checkbox is selected the installer will attempt to perform an automatic
 update. For more information please see
-[Upgrading from Previous Version](#upgrading-from-previous-version).
+[Upgrading on Windows](../Upgrading/OSSpecificInfo/Windows.md).
 
 #### Keep Backup
 
@@ -95,15 +95,6 @@ Select if you want the installer to create Desktop Icons that let you:
 - start the commandline client (arangosh)
 - start the database server (single user installation only)
 
-### Upgrading from Previous Version
-
-If you are upgrading ArangoDB from an earlier version you need to copy your old
-database directory [to the new default paths](#custom-install-paths). Upgrading
-will keep your old data, password and choice of storage engine as it is.
-Switching to the RocksDB storage engine requires an
-[export](../Programs/Arangoexport/README.md) and
-[reimport](../Programs/Arangoimport/README.md) of your data.
-
 ### Starting
 
 If you installed ArangoDB for multiple users (as a service) it is automatically

Documentation/Books/Manual/SUMMARY.md

@@ -312,6 +312,7 @@
   * [OS-specific Information](Upgrading/OSSpecificInfo/README.md)
     * [Upgrading on Linux](Upgrading/OSSpecificInfo/Linux.md)
     * [Upgrading on macOS](Upgrading/OSSpecificInfo/MacOS.md)
+    * [Upgrading on Windows](Upgrading/OSSpecificInfo/Windows.md)    
   * [Upgrading _Starter_ Deployments](Upgrading/Starter/README.md)  
   * [Upgrading Manual Deployments](Upgrading/Manually/README.md)
     * [Upgrading an Active Failover deployment](Upgrading/Manually/ActiveFailover.md)	

Documentation/Books/Manual/Upgrading/OSSpecificInfo/README.md

@@ -3,3 +3,4 @@ OS-specific Information
 
 - [Upgrading on Linux](Linux.md)
 - [Upgrading on macOS](MacOS.md)
+- [Upgrading on Windows](Windows.md)

Documentation/Books/Manual/Upgrading/OSSpecificInfo/Windows.md

@@ -0,0 +1,115 @@
+Upgrading on Windows
+====================
+
+As there are different ways to install ArangoDB on Windows, the upgrade
+method depends on the installation method that was used.
+
+In general, it will be needed to:
+
+- Install (or unpack) the new ArangoDB binaries on the system
+- Upgrade the current database (or perform a restore)
+- Optional (but suggested) to keep the system clean (unless there are specific
+  reasons to not do so): remove the old binaries from the system
+
+Some of the above steps may be done automatically, depending on your
+specifc situation.
+
+Upgrading via the Installer
+---------------------------
+
+If you have installed via the _Installer_, to upgrade:
+
+- Download the new _Installer_ and run it.
+- The _Installer_ will ask if you want to update your current database: select
+  the option "_Automatically update existing ArangoDB database_" so that the database
+  files will be upgraded.
+
+![Update Option](installer_upgrade.png)
+
+{% hint 'info' %} 
+Upgrading via the Installer, when the old data is kept, will keep your 
+password and choice of storage engine as it is.
+{% endhint %}
+
+- After installing the new package, you will have both packages installed.
+- You can uninstall the old one manually (make a copy of your old configuration
+file first).
+
+![Uninstall old version](both_installations.png)
+
+{% hint 'danger' %} 
+When uninstalling the old package, please make sure the option
+"_Delete databases with unistallation_" is **not** checked.
+{% endhint %}
+
+![Delete Option](installer_delete.png)
+
+{% hint 'danger' %} 
+When upgrading, the Windows Installer does not use the old configuration file
+for the installed _Single Instance_ but a new (default) one ([Issue #3773](https://github.com/arangodb/arangodb/issues/3773)).
+To use the old configuration, it is currently needed to:
+- Stop the server
+- Replace the new with the old confituration file
+- Restart the server
+{% endhint %}
+
+Manual upgrade of a 'ZIP archive' installation
+----------------------------------------------
+
+There are two ways to upgrade a _Single Instance_ that has been started
+from a _ZIP_ package:
+
+- In-Place upgrade
+- Logical upgrade
+
+### In-Place upgrade
+
+{% hint 'info' %} This method works easier if: 
+- You are using a data directory which is located outside of the directory 
+  created when extracting the _ZIP_  archive (data directory can be set via
+  the server option *--database.directory*)
+- You are using a configuration file which is located outside of the directory 
+  created when extracting the _ZIP_  archive (a configuration file can be passed via
+  the server option *--configuration*)
+{% endhint %}
+
+Assuming that:
+- Your data directory is _directory1_ (e.g. "D:\arango\data")
+- Your configuration file is _file_ (e.g. "D:\arango\conf\arangod.conf")
+- Your old binaries are on _directory2_ (e.g. "C:\tools\arangodb-3.4.0")
+
+to perform the upgrade of a _Single Instance_:
+
+1. Download and extract the new _ZIP_ package into a new directory (e.g
+   _directory3_ "C:\tools\arangodb-3.4.1")
+2. Stop your old server
+3. Start again the server (this time using the binary located in _directory3_)
+   passing:
+   - _directory1_ as *--database.directory*,
+   - _file_ as *--configuration*
+   - the option *--database.auto-upgrade* (so that the old data directory will
+     be upgraded)
+4. When the previous step is finished the server will stop automatically; you
+   can now start your server again as done in the previous step but without
+   passing the *--database.auto-upgrade* option
+5. Optionally remove the old server package by dropping the corresponding
+   directory when you are confident enough that all is working fine.
+   
+### Logical upgrade
+
+To perform the upgrade of a _Single Instance_:
+
+1. Download the new package and extract it on a different location than the
+   previous one
+2. Stop writes to the old server (e.g. block incoming connections)
+3. Take a backup of the data using _arangodump_
+4. Stop the old server
+5. Optional (depending on whether or not you modfied default confiugaration),
+   copy old ArangoDB configuration file to the new server (or just edit
+   the new configuration file)
+6. Start the new server (with a fresh data directory, by default it will be
+   inside the directory created when extracting the _ZIP_ archive)
+7. Restore the backup into the new server using _arangorestore_
+8. Re-enable the writes (e.g. allow again incoming connections)
+9. Optionally remove the old server package by dropping the corresponding
+   directory when you are confident enough that all is working fine.