A bit of background info first. We've been using Phabricator for about a year in our Vancouver office, and we've recently opened up an office on the other side of the country in Ottawa (where I am writing this from). Currently we're using a VPN to access the Phabricator instance (hosted in Vancouver) remotely. We make heavy use of Diffusion, Maniphest, Projects, Phriction, and more recently Differential.

The repositories we need in the Ottawa office are unlikely to be touched in the Vancouver office, and the connection is not always stable, so we've been exploring our options for hosting as much as possible locally. We've talked about using clustering to solve this, but I'm doubtful our particular use-case is accommodated, since the VPN link is not reliable and the bandwidth is kind of terrible.

It's probably not the typical use-case for clustering, so is this something you see as a reasonable solution? If not, is there any alternate solution you would recommend?

The proposed alternative at the moment is to host repositories locally and have the Vancouver office Phabricator instance observe them. I believe this would also result in reverting to using over-the-shoulder code reviews, or the manual ping-someone-in-slack approach. Unless the Arcanist and Differential workflow is still able to be used with observed repositories?