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The usage of Cassandra's internal keyspace "system"

The default Cassandra systems keyspace system is present in all Cassandra installations.

Judging from the output of the describe keyspace command the keyspace is used partly for "persistent metadata for the local node" (LocationInfo) and partly for "hinted handoff data".

  • What persistent metadata for the local node is stored in system/LocationInfo?
  • What is the definition of hinted handoff in Cassandra terminology?
  • What hinted handoff data is stored in the system keyspace?
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knorv Avatar asked Mar 30 '10 16:03

knorv


1 Answers

"Hinted handoff means that if a node that should receive a write is down, Cassandra will send that write to another node with a "hint" saying that when the destination node becomes available again, the write should be forwarded there."

After the answer on question two I believe the third question becomes obsolete (?)

And finally the first question: The token, cluster name, and whether the node is bootstrapped or not will be stored in system. (thanks driftx)

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Schildmeijer Avatar answered Sep 24 '22 10:09

Schildmeijer