On Tue, 14 Jan 2025 at 09:26, Baodi Shi <ba...@apache.org> wrote: > > hi, @lari and @enrico thanks for discuss. > > Yes, I agree that PR 9292 is a useful feature. > > https://pulsar.apache.org/contribute/release-policy/#compatibility-between-releases > > When I look at our compatibility strategy, what we promised is > compatibility from 3.0 -> 4.0 -> 3.0. > > Note that when the documentation mentions 3.0 and 4.0, I understand > that they are the latest versions of 3.0 and 4.0, not the earlier > ones. > > We need to ensure this, right?
When we say there's support for downgrading (rollback), it doesn't mean users don't need to take any action. We ensure downgrade compatibility by providing an upgrade guide that explains how to configure the system to allow rollbacks without losing state information. If we didn't do this, we'd always be stuck in the same situation whenever a new LTS version comes out. Let's start making progress: - keep PR 9292 as default - implement PR 23759 without changing the PR 9292 default - write a proper upgrade guide for Pulsar 4.0 where rollback considerations are explained Makes sense? -Lari
