Replication Factor Change

[Yulian Oifa <oi...@gmail.com>]

Hello to all.
I am planning to change replication factor from 1 to 3.
Will it cause data read errors in time of nodes repair?

Best regards
Yulian Oifa

RE: Replication Factor Change

[ae...@orange.com]

Hello,

If current CL = ONE, Be careful on production at the time of change replication factor, 3 nodes will be queried while data is being transformed ==> So data read errors!
De : Yulian Oifa [mailto:oifa.yulian@gmail.com]
Envoyé : jeudi 5 novembre 2015 16:02
À : user@cassandra.apache.org
Objet : Replication Factor Change

Hello to all.
I am planning to change replication factor from 1 to 3.
Will it cause data read errors in time of nodes repair?
Best regards
Yulian Oifa

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Re: Replication Factor Change

[Yulian Oifa <oi...@gmail.com>]

Hello
OK i got it , so i should set CL to ALL for reads, otherwise data may be
retrieved from nodes that does not have yet current record.
Thanks for help.
Yulian Oifa

On Thu, Nov 5, 2015 at 5:33 PM, Eric Stevens <mi...@gmail.com> wrote:

> If you switch reads to CL=LOCAL_ALL, you should be able to increase RF,
> then run repair, and after repair is complete, go back to your old
> consistency level.  However, while you're operating at ALL consistency, you
> have no tolerance for a node failure (but at RF=1 you already have no
> tolerance for a node failure, so that doesn't really change your
> availability model).
>
> On Thu, Nov 5, 2015 at 8:01 AM Yulian Oifa <oi...@gmail.com> wrote:
>
>> Hello to all.
>> I am planning to change replication factor from 1 to 3.
>> Will it cause data read errors in time of nodes repair?
>>
>> Best regards
>> Yulian Oifa
>>
>

Re: Replication Factor Change

[Eric Stevens <mi...@gmail.com>]

If you switch reads to CL=LOCAL_ALL, you should be able to increase RF,
then run repair, and after repair is complete, go back to your old
consistency level.  However, while you're operating at ALL consistency, you
have no tolerance for a node failure (but at RF=1 you already have no
tolerance for a node failure, so that doesn't really change your
availability model).

On Thu, Nov 5, 2015 at 8:01 AM Yulian Oifa <oi...@gmail.com> wrote:

> Hello to all.
> I am planning to change replication factor from 1 to 3.
> Will it cause data read errors in time of nodes repair?
>
> Best regards
> Yulian Oifa
>