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From Joseph Tech <jaalex.t...@gmail.com>
Subject Re: Read timeouts on primary key queries
Date Tue, 30 Aug 2016 11:40:26 GMT
Hi Patrick,

The nodetool status shows all nodes up and normal now. From OpsCenter
"Event Log" , there are some nodes reported as being down/up etc. during
the timeframe of timeout, but these are Search workload nodes from the
remote (non-local) DC. The RF is 3 and there are 9 nodes per DC.

Thanks,
Joseph

On Mon, Aug 29, 2016 at 11:07 PM, Patrick McFadin <pmcfadin@gmail.com>
wrote:

> You aren't achieving quorum on your reads as the error is explains. That
> means you either have some nodes down or your topology is not matching up.
> The fact you are using LOCAL_QUORUM might point to a datacenter mis-match
> on node count + RF.
>
> What does your nodetool status look like?
>
> Patrick
>
> On Mon, Aug 29, 2016 at 10:14 AM, Joseph Tech <jaalex.tech@gmail.com>
> wrote:
>
>> Hi,
>>
>> We recently started getting intermittent timeouts on primary key queries
>> (select * from table where key=<key>)
>>
>> The error is : com.datastax.driver.core.exceptions.ReadTimeoutException:
>> Cassandra timeout during read query at consistency LOCAL_QUORUM (2
>> responses were required but only 1 replica
>> a responded)
>>
>> The same query would work fine when tried directly from cqlsh. There are
>> no indications in system.log for the table in question, though there were
>> compactions in progress for tables in another keyspace which is more
>> frequently accessed.
>>
>> My understanding is that the chances of primary key queries timing out is
>> very minimal. Please share the possible reasons / ways to debug this issue.
>>
>> We are using Cassandra 2.1 (DSE 4.8.7).
>>
>> Thanks,
>> Joseph
>>
>>
>>
>>
>

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