Post by @jorijn
I completed a smooth Mastodon server migration this morning with only 8 minutes of downtime.
I prepared carefully; the web, streaming, and sidekiq components were active on the new cluster but connected to the old PostgreSQL and Redis, enabling an early DNS switch.
The switch involved promoting the streaming replica database to primary and syncing with redis-shake. I redeployed with the new settings and we were set to go.
All that on a Friday. :-)