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From Joe Alex <joe.m.a...@gmail.com>
Subject Question on Hinted Handoff
Date Mon, 01 Nov 2010 18:22:29 GMT
I am running cassandra 0.6.6
4 nodes with RF=3
Have set the InitialTokens manually
Loaded around 4 million records

Had a question why the following is happening

Node 4 was down when a new key 1005 was added (value 123).
Node 2 which is responsible for the key added a Hint for Node 4
Node 4 was brought back up and noticed the Hints Handed off and data
started showing up in Node 4
Noticed a ReadRepair also happenning
All fine so far

did a get and the value is 123
Node 2 returned the data, with background digest checks on Node 3 and
Node 4 (RF=3)

Now Node 2 (responsible for key 1005) was taken down
Key 1005 value was updated to A123 (ApplyRowMutation on Node 3 and Node 4).
Node 4 added a hint for Node 2

did a get and the value is A123
Node 3 returned the data, with background digest checks on Node 4
(RF=3 and Node 2 is down)

Now Node 2 is back up
Hints were handed off by Node 4

did a get and the value is the old value 123
Node 2 returned the data, with background digest checks on Node 3 and
Node 4 (RF=3)

Was expecting the latest write wins - A123 written on Node 4 to be in Node 2.
Any ideas ?

Now if Node 2 is down the old value A123 will be returned
Tried a repair when Node 2 was up and all Nodes got updated to the old data

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