You mean if, say, some verifiable metadata or a trusted third party stores that checksum? Sure. This is just pushing the what-has-committed
information to some other party, though, who will presumably face the same problem of requiring a majority for verifiable correctness. This is more or less what most people do in practice... using Paxos for critical state and piggybacking the rest of the system's consistency off of that.
(This is why Paxos is typically used only for critical clusterYep, I'm working on a config daemon a la Chubby or zookeeper, based on Paxos,
configuration/state, not regular data.)
that does just this. :)
Cool. Do you have a URL? I'd be interested in seeing how you diverge from classic paxos. For Ceph's monitor daemon, the main requirements (besides strict correctness guarantees) were scalable (distributed) read access, and a history of state changes. Nothing too unusual.