Slack digest for #general - 2018-02-08

[Apache Pulsar Slack <ap...@gmail.com>]

2018-02-08 11:57:11 UTC - bsideup: Does Pulsar store critical data in ZooKeeper? Or ZooKeeper cluster can be ephemeral?
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2018-02-08 12:10:07 UTC - Ivan Kelly: the data in zookeeper is critical, yes
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2018-02-08 12:11:22 UTC - Ivan Kelly: the metadata for managed ledgers and ledgers are stored there
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2018-02-08 12:12:10 UTC - Ivan Kelly: what kind of system makes zookeeper ephemeral, out of interest?
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2018-02-08 12:23:56 UTC - bsideup: Just doing Cloud Deployment planning, qas hoping that ZK is only used for the election and coordination 
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2018-02-08 12:48:40 UTC - Ivan Kelly: if the system provides the ordering guarantees the pulsar does, something needs to be doing concensus and keeping the results around.
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2018-02-08 12:50:22 UTC - Ivan Kelly: some systems like hbase appear to get around it, but really it's relying on the HDFS namenode for the concensus
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2018-02-08 12:50:39 UTC - Ivan Kelly: and I think that uses a mix of it's own raft implementation and zookeeper
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