Last modified: 2014-10-24 14:50:38 UTC
File:SomeImage links on en-beta correctly find images from http://commons.wikimedia.beta.wmflabs.org , e.g. http://en.wikipedia.beta.wmflabs.org/wiki/File:A_nice_picture.jpg shows the file info from commons-beta and links to it on upload-beta. Yay! But links in the explanation "This is a file from the Wikimedia Commons. Information from its description page there is shown below. Commons is a freely licensed media file repository. You can help." go to production commons, not commons-beta. I think this happens because the http://en.wikipedia.beta.wmflabs.org/wiki/MediaWiki:Sharedupload-desc-here message imported from enwiki either hardcodes commons.wikimedia.org, or doesn't support its override. There should be a template or magic word for {{INSTANTCOMMONSNAME}} {{INSTANTCOMMONSURL}}, but I'm far from expert on the setup.
The analysis is correct, the image description comes from production commons and thus reuse whatever template might be set there. When placed on the beta cluster, the URL is not consistent indeed, but I don't think it is worth engineering a solution.