Edit Geo nodes content to comply with SSOT guidelines

doc/user/admin_area/geo_nodes.md

+---
+type: howto
+---
+
 # Geo nodes admin area **[PREMIUM ONLY]**
 
-For more information about setting up GitLab Geo, read the
-[Geo documentation](https://docs.gitlab.com/ee/administration/geo/replication/index.html).
+You can configure various settings for GitLab Geo nodes. For more information, see
+[Geo documentation](https://docs.gitlab.com/ee/administration/geo/replication/index.md).
 
-When you're done, you can navigate to **Admin area > Geo** (`/admin/geo/nodes`).
+On the primary node, go to **Admin area > Geo**. On secondary nodes, go to **Admin area > Geo > Nodes**.
 
 ## Common settings
 
@@ -68,3 +72,15 @@ a unique `name` is set for each Geo node. The `gitlab.rb` setting
 
 The load balancer must use sticky sessions in order to avoid authentication
 failures and cross site request errors.
+
+<!-- ## Troubleshooting
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