Techniques to ensure cluster wide consistency at distributed databases -


after reading an excellent article role of logs in distributed file systems logging seems me answer cluster-wide-consistency of distributed databases , data integration problem.

does distributed systems use logs synchronization, consistency, replication , recovery purposes? or differ in format/protocol of log?

could u please provide alternative ways of cluster-wide-consistency in distributed databases?

hbase , bigtable both give example of logs in modern databases.

what did mean? other databases doesn't use logs consistency purposes?


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