OVH down

[minrk]

The whole OVH cluster is down, apparently the project is suspended for some reason. We've received no communication about it, but are pursuing via email.

Because OVH was the 'prime' member, this meant mybinder.org was unavailable. The 'prime' member does two things:

1. it serves the HTML pages for mybinder.org (via proxy, not directly)
2. it will still be routed requests when it's full/unhealthy, relying on its own quota to limit traffic

Thanks to the separation of the federation-redirect from the main cluster when we had to shut down most of GKE, making another member prime is all we needed to do (#2862) to get mybinder.org back up, since no member directly serves mybinder.org.

And thanks to @manics and @stevejpurves, we actually have another candidate in curvenote, which has filled in as the prime member, so mybinder.org is back up at diminished capacity, rather than completely unavailable. GESIS probably shouldn't be prime because it serves a custom main page at https://notebooks.gesis.org/binder/

[minrk]

OVH is back up, we are still trying to understand what happened.