Cassandra System_Auth keyspace with RF=1 gets replicated to new nodes

1
votes

As part of a POC. I have a 1 node cassandra cluster with system_auth keyspace RF=1.

I added a second node to this cluster(with empty data/commitlog/saved_cache directory) and I notice user credentials are replicated to the new node. Since RF=1 for existing node, I don't expect it to replicate to new node.

Any reason why ?

Cassandra Version : 2.1.8

1
cassandradatastaxcassandra-2.1

1 Answers

2
votes

For most system_auth queries, Cassandra uses a consistency level of LOCAL_ONE and uses QUORUM for the default cassandrasuperuser. If both nodes are up, you will be able to see the data and login without any problem. Also you added second node with empty commit log and saved caches, but if you copied the rest of the data form the original node the data will be there, including system_auth.