I have some basic question about monitor and paxos relationship: As the documents says, Ceph monitor contains cluster map, if there is any change in the state of the cluster, the change is updated in the cluster map. monitor use paxos algorithm to create the consensus among monitors to establish a quorum. And when we talk about the Paxos algorithm, documents says that monitor writes all changes to the Paxos instance and Paxos writes the changes to a key/value store for strong consistency. #1: I am unable to understand what actually the Paxos algorithm do? all changes in the cluster map are made by Paxos algorithm? how it create a consensus among monitors My assumption is: cluster map is updated when OSD report monitor about any changes, there is no role of Paxos in it. Paxos write changes made only for the monitors. Please somebody elaborate at this point. #2: why odd no. of monitors are recommended for production cluster, not even no.? Please help me to clarify these points. Regards Pragya Jain -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.ceph.com/pipermail/ceph-users-ceph.com/attachments/20140829/4361722e/attachment.htm>
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