Hi, thanks a lot for answer :) Gossip is a peer-to-peer communication protocol in which nodes periodically exchange state information about themselves and about other nodes they know about.
unreachableNodes = probe.getUnreachableNodes(); ---> i.e if node don't publish heartbeats on x seconds (using gossip protocol), it's therefore marked 'DN: down' ? That's it? 2016-08-11 13:51 GMT+01:00 Romain Hardouin <romainh...@yahoo.fr>: > Hi Jean Paul, > > Yes, the gossiper is used. Example with down nodes: > 1. The status command retrieve unreachable nodes from a NodeProbe > instance: https://github.com/apache/cassandra/blob/trunk/ > src/java/org/apache/cassandra/tools/nodetool/Status.java#L64 > 2. The NodeProbe list comes from a StorageService proxy: > https://github.com/apache/cassandra/blob/trunk/src/java/ > org/apache/cassandra/tools/NodeProbe.java#L438 > 3. The proxy calls the Gossiper singleton: https://github.com/ > apache/cassandra/blob/trunk/src/java/org/apache/cassandra/ > service/StorageService.java#L2681 > > Best, > > Romain > > Le Jeudi 11 août 2016 14h16, jean paul <researche...@gmail.com> a écrit : > > > Hi all, > > > > *$nodetool status*Datacenter: datacenter1 > ======================= > Status=Up/Down > |/ State=Normal/Leaving/Joining/ Moving > -- Address Load Tokens Owns (effective) Host > ID Rack > > > *UN 127.0.0.1 83.05 KB 256 100.0% > 460ddcd9-1ee8-48b8-a618- c076056aad07 rack1* > *The nodetool command* shows the status of the node (UN=up, DN=down): > > Please i'd like to know how this command works and is it based on gossip > protocol or not ? > > Thank you so much for explanations. > Best regards. > > > > >
