Hi ceph-devel, Recently we are trying the upgrade from Firefly to Giant and it goes pretty smoothly, however, the problem is that it does not support rollback and seems like that is by design. For example, there is new feature flag / metadata [1] added in the new version and they are persisted. As a result, the old version of software does not recognize those values and will crash themselves. Ideally we never rollback, but for unknown reasons we couldn't fix in a timely manner, we might want to rollback first. Is that something we will consider to handle? [1] https://github.com/ceph/ceph/commit/1fe8b846641486cc294fe7e1d2450132c38d2dba Thanks, Guang -- To unsubscribe from this list: send the line "unsubscribe ceph-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html