Add Migration explanation to add-on doc

content/doc/addons/mongodb/_index.md

@@ -60,6 +60,8 @@ The process consists in three steps:
 
 Encryption at rest is available on MongoDB. You can have more information on the [dedicated page]({{< ref "doc/administrate/encryption-at-rest.md" >}})
 
+{{% content/dbMigration %}}
+
 ## Can I use Mongo Ops Manager on Clever Cloud?
 
 To be able to use [Mongo Ops Manager](https://www.mongodb.com/products/ops-manager), you'll need a valid MongoDB Enterprise Advanced subscription and to deploy a [Linux version of their manager solution](https://www.mongodb.com/try/download/ops-manager). If you haven't purchased any license from MongoDB and you are using the Community version, you might be looking for a similar service for your databases.

content/doc/addons/mysql/_index.md

@@ -36,6 +36,8 @@ If you want to import your **SQL** dump, you can use several methods:
 
 If you need to import a very large dump, contact [Clever Cloud Support](https://console.clever-cloud.com/ticket-center-choice).
 
+{{% content/dbMigration %}}
+
 ## Direct access
 
 {{< callout type="warning">}}

content/doc/addons/postgresql/_index.md

@@ -34,6 +34,8 @@ Some applications require a non-empty database to run properly. If you want to i
 2. Command line tool for PostgreSQL administration like `psql`
 3. Any PostgreSQL client such as [pgAdmin](https://www.pgadmin.org/)
 
+{{% content/dbMigration %}}
+
 ## Direct access
 
 A proxy serves all dedicated PostgreSQL databases. In some cases, this can add some latency between applications and their database. If this is an issue, you can generate a direct hostname and port for the add-on to bypass the proxy, using the "Generate direct hostname and port" button in the add-on dashboard.

content/doc/addons/redis.md

@@ -28,6 +28,8 @@ The version currently installed by the add-on are the following :
 
 A backup is a `tar.gz` archive containing both the `.rdb` and `.aof` files. You can extract this archive and run `redis-server` in the extracted folder to access data.
 
+{{% content/dbMigration %}}
+
 ## Leader / follower topology
 
 By default, all redis add-ons are configured as leaders. You can set up a redis add-on as a follower from the add-on panel (in the "Add-on information" tab). You need to set the leader

layouts/shortcodes/content/dbMigration.md

@@ -0,0 +1,10 @@
+## Migrate your database
+
+Clever Cloud provides an add-on Migration/Upgrade tool. You can access it from the [Console](https://console.clever-cloud.com), in the left menu when an add-on is selected. It allows to choose a higher plan, a new version or another deployment zone.
+
+A migration process creates new instances, moves your data into it and stops the old ones if the process ended correctly. In case of a failure during migration, new instances are deleted and you go back to the original ones.
+The duration may vary depending on how much data your add-on has. Your database becomes read only for the entire duration.
+
+If you want to restart your add-on or update to the last supported version of the current branch, migrate it to the same plan, version, zone. 
+
+- [More Clever Cloud Tips and Tricks](/developers/doc/best-practices/tips_and_tricks/)