NServiceBus.Gateway.RavenDB upgrade guide (#7783)

* NServiceBus.Gateway.RavenDB upgrade guide

* Align title

Author: danielmarbach

menu/menu.yaml

@@ -1174,6 +1174,12 @@
         Title: Version 4 to 5
       - Url: persistence/upgrades/ravendb-3to4
         Title: Version 3 to 4
+    - Title: RavenDB Gateway Storage
+      Articles:
+      - Url: persistence/upgrades/ravendb-gateway-4to5
+        Title: Version 4 to 5
+      - Url: persistence/upgrades/ravendb-gateway-1to2
+        Title: Version 1 to 2        
     - Title: SQL
       Articles:
       - Url: persistence/upgrades/sql-client4

persistence/upgrades/ravendb-gateway-4to5.md

@@ -0,0 +1,22 @@
+---
+title: NServiceBus Gateway RavenDB Persistence Upgrade from 4 to 5
+summary: Instructions on how to upgrade NServiceBus.Gateway.RavenDB from version 4 to version 5
+component: GatewayRavenDB
+related:
+- nservicebus/gateway
+- nservicebus/gateway/ravendb
+reviewed: 2025-08-26
+isUpgradeGuide: true
+upgradeGuideCoreVersions:
+ - 9
+---
+
+## RavenDB Client Upgrade
+
+NServiceBus.Gateway.RavenDB version 5 introduces support for [RavenDB.Client 6.2.9 or higher](https://www.nuget.org/packages/RavenDB.Client).
+
+RavenDB clients are forward-compatible starting with version 4.2, meaning a newer client can connect to a server of the same or higher version. However, if your servers are running a version prior to 6, upgrading the client requires extra care.
+
+In this case, review both the [RavenDB client breaking changes](https://docs.ravendb.net/6.0/migration/client-api/client-breaking-changes/) and the [RavenDB server breaking changes](https://docs.ravendb.net/6.0/migration/server/server-breaking-changes/) to ensure compatibility before upgrading.
+
+If your servers are already on RavenDB 6 or higher, you can safely upgrade the client library after consulting the [RavenDB client breaking changes](https://docs.ravendb.net/6.0/migration/client-api/client-breaking-changes/) without requiring immediate server changes.