update upgrading docs

diff --git a/server/sonar-docs/src/pages/setup/upgrading.md b/server/sonar-docs/src/pages/setup/upgrading.md
index 337efde9aff9b0f7fe929e752bcc507866b1584c..2d3ca7f7def4b0f20445b19df841253e873c05d8 100644 (file)
--- a/server/sonar-docs/src/pages/setup/upgrading.md
+++ b/server/sonar-docs/src/pages/setup/upgrading.md
@@ -1,45 +1,18 @@
 ---
-title: Upgrade the Server
+title: Upgrade Guide
 url: /setup/upgrading/
 ---
-
-## SonarQube Version Number Format
-Before upgrading, it helps to understand how SonarQube version numbers work. Version numbers have up to three digits with each digit representing part of the release cycle:
-
-![SonarQube version number format](/images/version.png)
-
-**Major version number**  
-The major version number represents a series of releases with high-level objectives for the release cycle. It's incremented with the release following an LTS version (for example, the release following 7.9 LTS was 8.0).
-
-**Minor version number**  
-The minor version number corresponds to incremental functional changes within a major release cycle. At the time of an LTS release, the release cycle is closed and the minor version number is frozen.
-
-**Patch release number**  
-Only on LTS versions, the patch release number represents patches to an LTS that fixed blocker or critical problems. The patch release number isn't considered in your upgrade migration path, and your migration path is the same no matter which patch number you are on.
-
-## Migration Path
-Upgrading across multiple non-LTS versions is handled automatically. However, if there's one or multiple LTS versions in your migration path, you must first migrate to each intermediate LTS and then to your target version, as shown in **Example 3** below.
-
-[[info]]
-|If you're migrating from an earlier patch version of an LTS, you can upgrade directly to the next LTS. You don't need to install any intermediate patch versions.
-
-**Migration Path Examples**:
-
-**Example 1** – From 8.1 > 9.0, the migration path is 8.1 > 8.9.1 LTS > 9.0  
-**Example 2** – From 8.2 > 8.9 LTS, the migration path is 8.2 > the latest 8.9 LTS patch.  
-**Example 3** – From 6.7.7 LTS > 8.9 LTS, the migration path is 6.7.7 LTS > 7.9.6 LTS > the latest 8.9 LTS patch.
-
-## Upgrade Guide
-
 This is a generic guide for upgrading across versions of SonarQube. Carefully read the [Release Upgrade Notes](/setup/upgrade-notes/) of your target version and of any intermediate version(s).
 
+To understand the upgrading process and important concepts, see the [Upgrading Concepts](/setup/upgrading-concepts] documentation. 
+
 [[warning]]
 | Before you start, back up your SonarQube Database. Upgrade problems are rare, but you'll want the backup if anything does happen.
 
-### Database disk usage recommendations
+## Database disk usage recommendations
 During your upgrade, tables may be duplicated to speed up the migration process, and this could cause your database disk usage to double. Because of this, we recommend that your database disk usage is below 50% before starting a migration.
 
-### Upgrading from the ZIP file
+## Upgrading from the ZIP file
 
 1. Download and unzip the SonarQube distribution of your edition in a fresh directory, let's say `$NEW_SONAR_HOME`
 2. Manually install additional plugins that are compatible with your version of SonarQube. Use the [Compatibility Matrix](https://docs.sonarqube.org/display/PLUG/Plugin+Version+Matrix) to ensure that the versions you install are compatible with your server version. Simply copying plugins from the old server to the new is not recommended; incompatible or duplicate plugins could cause startup errors. Analysis of all languages provided by your edition is available by default without plugins.
@@ -50,7 +23,7 @@ If you are using the Oracle DB, copy its JDBC driver into `$NEW_SONAR_HOME/exten
 6. Browse to `http://yourSonarQubeServerURL/setup` and follow the setup instructions
 7. Reanalyze your projects to get fresh data
 
-### Upgrading from the Docker image
+## Upgrading from the Docker image
 
 [[info]]
 | If you're upgrading with an Oracle database or you're using additional plugins, you can reuse your extensions volume from the previous version to avoid moving plugins or drivers. Use the [Compatibility Matrix](https://docs.sonarqube.org/display/PLUG/Plugin+Version+Matrix) to ensure that your plugins are compatible with your version. Analysis of all languages provided by your edition is available by default without plugins.
@@ -82,7 +55,7 @@ To upgrade SonarQube using the Docker image:
 
 4. Reanalyze your projects to get fresh data.
 
-#### **From 8.9.x LTS to another 8.9.x LTS**
+### **From 8.9.x LTS to another 8.9.x LTS**
 
 No specific Docker operations are needed, just use the new tag.