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From Joe Alex <joe.m.a...@gmail.com>
Subject Re: Question on Hinted Handoff
Date Tue, 02 Nov 2010 13:32:46 GMT
Thanks, that clarifies why HH did not work, So have to use .7. Is
there .6.7 ? I am using .6.6 now.
I did see the log entry in Node 4, adding a Hint for Node 2 and when
Node 2 came up noticed a log entry in Node 4 that 1 row Handed Off -
so I thought it was working.

About RR - a read in Node 1 or Node 2 indicated a RR (see log entry
above) was happening. But dont think that ever happened. Those entries
keep repeating every time a read in Node 1 and 2 and kept giving old
data.

AES assuming Anti-Entropy - Tried nodetool repair, this also did not
fix the issue.

The only time I saw it being fixed was a read to Node 3 or Node 4
(mostly Node 3 which acted as responsible when Node 2 was down)  and
then 2nd reads to Node 2 started showing the latest data.

Do you think RR and AES should have definitely worked ?


On Tue, Nov 2, 2010 at 1:01 AM, Brandon Williams <driftx@gmail.com> wrote:
> On Mon, Nov 1, 2010 at 8:28 PM, Joe Alex <joe.m.alex@gmail.com> wrote:
>>
>> My expectation was even though Node 2 was down key written to Node 3
>> or 4 should be updated in Node 2 using Hint and the subsequent reads
>> to Node 1 or Node 2 itself should have got the latest value
>
> Your expectation is correct, unfortunately I broke HH in 0.6.5 with a bad
> backport and it affects
> 0.6.6: https://issues.apache.org/jira/browse/CASSANDRA-1656
> But, that is why we have Read Repair and AES.  It's worth noting that HH is
> best effort anyway, if Node 2 was down but the failure detector hadn't
> noticed yet, no hint would be created and you'd have the same behavior.
> -Brandon

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