Re: system_auth replication factor in Cassandra 2.1

[kurt greaves]

For that many nodes mixed with vnodes you probably want a lower RF than N
per datacenter. 5 or 7 would be reasonable. The only down side is that auth
queries may take slightly longer as they will often have to go to other
nodes to be resolved, but in practice this is likely not a big deal as the
data will be cached anyway.