I have just found this interesting project for Rails after a lot of research:

https://github.com/postalserver/postal

I wonder if there are any other promising projects out there. The idea is to have a scalable service like Sendgrid, Postmark or AWS SES, .... but self-hosted.

I have a server with Ubuntu 22.04 and comes with Redis 6.0.

The Redis server is running in production.

Is it possible to upgrade Redis from v6 to v7 in-place on Ubuntu 22.04? Or I need to create a new server?