> On Jun 9, 2018, at 10:28 PM, onmstester onmstester <onmstes...@zoho.com>
> wrote:
>
>
> I'm using RF=2 (i know it should be at least 3 but i'm short of resources)
> and WCl=ONE and RCL=ONE in a cluster of 10 nodes in a insert-only scenario.
> The problem: i dont want to use nodetool repair because it would put hige
> load on my cluster for a long time, but also i need data consistency
> and fault tolerance in a way that:
> if one of my nodes fails:
> 1. there would be no single record data loss
This requires write > 1
> 2. write/read of data would be continued with no problem
>
This requires more replicas in the ring than the number of replicas requires
for reads and writes
> I know that current config won't satisfy No.1, so changed the Write
> Consistensy Level to ALL and to satisfy No.2, i'm catching exceptions of
> "1 replicas needed but 2 required", write those records again with WCL = ONE
> and put them somewhere for rewrite later with WCL=2.
> Is there anything wrong with this workaround? any better solution (Strong
> requirements: I can't change the RF, The system should tolerate 1 node
> failure with no data loss and no read/write failure)
Sorta works, but it’s dirty and a lot of edge cases. Depending on the budget
and value of data, maybe it’s ok, but I wouldn’t trust it to be good enough for
critical use cases
The transient replication work that Ariel is doing
(https://issues.apache.org/jira/browse/CASSANDRA-14404) will likely benefit you
here in 4.0 (but it will require you to run repair).
