Known issue: --cluster.upgrade should not be set on DB-Servers (#827)

Author: Simran-B

site/content/3.12/release-notes/version-3.12/known-issues-in-3-12.md

@@ -29,6 +29,7 @@ Note that this page does not list all open issues.
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 | **Date Added:** 2019-05-16 <br> **Component:** arangod <br> **Deployment Mode:** All <br> **Description:** Bugfix release upgrades such as 3.4.4 to 3.4.5 may not create a backup of the database directory even if they should. Please create a copy manually before upgrading. <br> **Affected Versions:** 3.4.x, 3.5.x, 3.6.x, 3.7.x, 3.8.x, 3.9.x, 3.10.x, 3.11.x, 3.12.x <br> **Fixed in Versions:** - <br> **Reference:** [arangodb/planning#3745](https://github.com/arangodb/planning/issues/3745) (internal) |
 | **Date Added:** 2023-06-06 <br> **Component:** arangod <br> **Deployment Mode:** Cluster <br> **Description:** During a cluster upgrade while the supervision is deactivated (maintenance mode), upgraded DB-Server nodes are incorrectly reported to still have the old server version. The versions are visible in the Agency as well as in the **Nodes** section of the web interface. <br> **Affected Versions:** 3.9.x, 3.10.x, 3.11.x, 3.12.x <br> **Fixed in Versions:** - <br> **Reference:** [BTS-1409](https://arangodb.atlassian.net/browse/BTS-1409) (internal) |
+| **Date Added:** 2025-11-10 <br> **Component:** arangod <br> **Deployment Mode:** Cluster <br> **Description:** If the startup option setting `--cluster.upgrade=online` is combined with `--database.auto-upgrade=true` on a DB-Server, upgrading to v3.12.6 fails. The `--cluster.upgrade` startup option should generally not be used for DB-Servers as it is for Coordinators only. From the hotfix version v3.12.6-1 onward, the option is properly ignored by DB-Servers. <br> **Affected Versions:** 3.12.6 <br> **Fixed in Versions:** 3.12.6-1 <br> **Reference:** [BTS-2246](https://arangodb.atlassian.net/browse/BTS-2246) (internal) |
 
 ## Hot Backup
 

site/content/3.13/release-notes/version-3.12/known-issues-in-3-12.md

@@ -29,6 +29,7 @@ Note that this page does not list all open issues.
 |------------|
 | **Date Added:** 2019-05-16 <br> **Component:** arangod <br> **Deployment Mode:** All <br> **Description:** Bugfix release upgrades such as 3.4.4 to 3.4.5 may not create a backup of the database directory even if they should. Please create a copy manually before upgrading. <br> **Affected Versions:** 3.4.x, 3.5.x, 3.6.x, 3.7.x, 3.8.x, 3.9.x, 3.10.x, 3.11.x, 3.12.x <br> **Fixed in Versions:** - <br> **Reference:** [arangodb/planning#3745](https://github.com/arangodb/planning/issues/3745) (internal) |
 | **Date Added:** 2023-06-06 <br> **Component:** arangod <br> **Deployment Mode:** Cluster <br> **Description:** During a cluster upgrade while the supervision is deactivated (maintenance mode), upgraded DB-Server nodes are incorrectly reported to still have the old server version. The versions are visible in the Agency as well as in the **Nodes** section of the web interface. <br> **Affected Versions:** 3.9.x, 3.10.x, 3.11.x, 3.12.x <br> **Fixed in Versions:** - <br> **Reference:** [BTS-1409](https://arangodb.atlassian.net/browse/BTS-1409) (internal) |
+| **Date Added:** 2025-11-10 <br> **Component:** arangod <br> **Deployment Mode:** Cluster <br> **Description:** If the startup option setting `--cluster.upgrade=online` is combined with `--database.auto-upgrade=true` on a DB-Server, upgrading to v3.12.6 fails. The `--cluster.upgrade` startup option should generally not be used for DB-Servers as it is for Coordinators only. From the hotfix version v3.12.6-1 onward, the option is properly ignored by DB-Servers. <br> **Affected Versions:** 3.12.6 <br> **Fixed in Versions:** 3.12.6-1 <br> **Reference:** [BTS-2246](https://arangodb.atlassian.net/browse/BTS-2246) (internal) |
 
 ## Hot Backup