Add note about image name structure to custom registry section
@@ -250,7 +250,13 @@ If you setup your own local registry using
and can handle these without any additional configuration
beyond `registry.url`.
+.. important::
+ BinderHub has a hard dependency on the `gcr.io` image name structure: `gcr.io/<project-id>/<prefix>-name:tag`.
+ Hence, your `image_prefix` field should be set to: `your-registry.io/<some-project-name>/<prefix>-`.
+
+ `<some-project-name>` can be completely arbitrary and/or made-up.
+ Without this, you may find that your BinderHub always rebuilds images instead of pulling them from the registry.
Install BinderHub
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