In scenario 2 it's lost, if both nodes die and get replaced entirely
there's no history anywhere that the write ever happened, as it wouldn't be
in commitlog, memtable, or sstable in node 3. Surviving that failure
scenario of two nodes with same data simultaneously failing requires upping
CL or RF, or spreading across 3 racks, if the situation you're trying to
avoid is rack failure (which im guessing it is from the question setup)

On Thu, May 2, 2019 at 2:25 PM Ben Slater <ben.sla...@instaclustr.com>
wrote:

> In scenario 2, if the row has been written to node 3 it will be replaced
> on the other nodes via rebuild or repair.
>
> ---
>
>
> *Ben Slater**Chief Product Officer*
>
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> On Fri, 3 May 2019 at 00:54, Fd Habash <fmhab...@gmail.com> wrote:
>
>> C*: 2.2.8
>>
>> Write CL = LQ
>>
>> Kspace RF = 3
>>
>> Three racks
>>
>>
>>
>> A write gets received by node 1 in rack 1 at above specs. Node 1 (rack1)
>> & node 2 (rack2)  acknowledge it to the client.
>>
>>
>>
>> Within some unit of time, node 1 & 2 die. Either ….
>>
>>    - Scenario 1: C* process death: Row did not make it to sstable (it is
>>    in commit log & was in memtable)
>>    - Scenario 2: Node death: row may be have made to sstable, but nodes
>>    are gone (will have to bootstrap to replace).
>>
>>
>>
>> Scenario 1: Row is not lost because once C* is restarted, commit log
>> should replay the mutation.
>>
>>
>>
>> Scenario 2: row is gone forever? If these two nodes are replaced via
>> bootstrapping, will they ever get the row back from node 3 (rack3) if the
>> write ever made it there?
>>
>>
>>
>>
>>
>> ----------------
>> Thank you
>>
>>
>>
>

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