Hi! Most tools query just a single db at a time, so I don't think this will be a massive problem. However some such as Global Contribs and GUC can theoretically query all of them from a single request. Creating new connections on-the-fly seems doable in production, the issue is how to work on these tools in a local environment. Currently the recommendation is to use a SSH tunnel to the desired host, such as enwiki.analytics.db.svc.eqiad.wmflabs. Surely we can't do this same port forwarding for 900+ connections.
Any ideas? Perhaps there's some way to make a host that automatically forwards to the correct one, solely for developer use? Or will development of such global tools need to happen in the Cloud Services environment?