Hi We have to use Cassandra with RF=2 (don't ask why...). There are two datacenters (RF=2 in each datacenter). Also we use Astyanax as a client library. In general we want to achieve strong consistency. Read performance is important for us, that's why we perform writes with LOCAL_QUORUM and reads with ONE. If one server is down, we automatically switch to Writes.ONE, Reads.ONE only for that replica which has failed node (we modified Astyanax to achieve that). When the server comes back, we turn back Writes.LOCAL_QUORUM and Reads.ONE, but, of course, we see some inconsistencies during the switching process and some time after (when hinted handnoff works).
Basically I don't have any questions, just want to share our "ugly" failover algorithm, to hear your criticism and may be advise on how to improve it. Unfortunately we can't change replication factor and most of the time we have to read with consistency level ONE (because we have strict requirements on read performance). Thank you!
