> It seems to me that with 2 datacenters, if one datacenter is lost,
> the reads/writes to cassandra will fail in the surviving datacenter
> because of the N/2 + 1 distribution of replicas. In other words, you
> need more than half of the replicas to respond but in the case of a
> datacenter los
> I think there's a flaw in your logic. Take the following scenario:
Ok, so sorry if I was being unclear. Yes, if you have one out of two
copies in data center B and the remainder in A, then A will be able to
continue operating qt QUOROM in the event of a partition. But B still
won't, so you have
I think there's a flaw in your logic. Take the following scenario:
- you use QUORUM for reads and QUROUM for writes
- you have 2 datacenters (DC1, DC2), with 3 servers in each (so 6 nodes
total).
- you set replication factor to 3
- you use RackAwareStrategy
So, you have DC1-S1, DC1-S2, DC1-S3, DC
> Thanks a lot Peter. So basically we would need to choose a
> consistency other than QUORUM. I think in our case consistency is
> not necessarily an issue since our data is write-once, read-many
> (immutable data). I suppose having a replication factor of 4 would
> result in two nodes in ea
Thanks a lot Peter. So basically we would need to choose a
consistency other than QUORUM.I think in our case consistency is
not necessarily an issue since our data is write-once, read-many
(immutable data). I suppose having a replication factor of 4 would
result in two nodes in each datacen
>> Is my logic wrong here? Is there a way to ensure the nodes in the
>> alive datacenter respond successfully if the second datacenter is
>> lost? Anyone have experience with this kind of problem?
>
> It's impossible to achieve the consistency and availability at the
> same time. See:
(Assuming
> Is my logic wrong here? Is there a way to ensure the nodes in the
> alive datacenter respond successfully if the second datacenter is
> lost? Anyone have experience with this kind of problem?
It's impossible to achieve the consistency and availability at the
same time. See:
http://en.wikip
Hi cassandra experts -
We're planning a cassandra cluster across 2 datacenters
(datacenter-aware, random partitioning) with QUORUM consistency.
It seems to me that with 2 datacenters, if one datacenter is lost,
the reads/writes to cassandra will fail in the surviving datacenter
because of the N
