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From Bryan Talbot <btal...@aeriagames.com>
Subject Re: Reading old data problem
Date Fri, 01 Mar 2013 02:11:00 GMT
On Thu, Feb 28, 2013 at 5:08 PM, Víctor Hugo Oliveira Molinar <
vhmolinar@gmail.com> wrote:

> Ok guys let me try to ask it in a different way:
>
> Will repair totally ensure a data synchronism among nodes?


If there are no writes happening on the cluster then yes.  Otherwise, the
answer is "it depends" since all the normal things that lead to
inconsistencies can still happen.




>
> Extra question:
> Once I write at CL=All, will C* ensure that I can read from ANY node
> without an inconsistency? The reverse state, writing at CL=One but reading
> at CL=All will also ensure that?
>
>

You can get consistent behavior if CL.read + CL.write > RF.  So since you
have just 2 nodes and RF=2, you'd need to have at least CL.read=2 and
CL.write=1 or CL.read=1 and CL.write=2.

-Bryan



>
>
> On Wed, Feb 27, 2013 at 11:24 PM, Víctor Hugo Oliveira Molinar <
> vhmolinar@gmail.com> wrote:
>
>> Hello, I need some help to manage my live cluster!
>>
>> I'm  currently running a cluster with 2 nodes, RF:2, CL:1.
>> Since I'm limited to hardware upgrade issues, I'm not able to increase my
>> ConsitencyLevel for now.
>>
>> Anyway, * *I ran a full repair on each node of the cluster followed by a
>> flush. Although I'm still reading old data when performing queries.
>>
>> Well it's know that I might read old data during normal operations, but
>> shouldnt it be sync after the full antientropy repair?
>> What I'm missing?
>>
>> Thanks in advance!
>>
>
>

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