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If the LogCabin servers clean these independently, the set of tombstones and client responses on each replica may be different. In that case, I think only the log entries could be covered in a checksum.
John and Diego discussed this on 2012-03-26. We concluded that checksumming just the live entries (and no tombstones or client responses) would provide most of the benefit, and we shouldn't introduce much more complexity to increase checksum coverage for now.
Problem 2: When checksums don't match
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