系统和 system_schema :
Don't have to change strategy of keyspace system and system_schema because
its not user modifiable
dse_leases:
1) A replication factor of 1 is suitable for development and testing on a
single node only, but never in a production environment.
2) For production clusters, increase the replication factor to at least 3
for each logical datacenter that is running analytics.
dse_system:
DSE uses a default replication strategy of "EverywhereStrategy" for the
dse_system keyspace.The best approach is to keep the DSE node in the
cluster and then alter the replication strategy for the dse_system
keyspace to one that is understood by all nodes
(a) ALTER KEYSPACE dse_system WITH replication = {'class': 'NetworkTopologyStrategy', 'DC1':1 ,'DC2':1};
dse_perf:
DataStax Enterprise uses the dse_perf keyspace for storing performance
metrics data.By default DataStax Enterprise writes performance metrics
data with consistency level ONE and writes are performed asynchronously.
Set the replication factor based depending on your environment:
(a) ALTER KEYSPACE "dse_perf" WITH REPLICATION = {'class' : 'NetworkTopologyStrategy', 'dc1' : 3, 'dc2' : 2};
system_auth 和 dse_security :
Cassandra uses the system_auth and dse_security keyspaces for storing
security authentication and authorization information. DataStax
Enterprise uses the system_auth keyspace when you enable any kind of
authentication. DataStax Enterprise uses the dse_security keyspace only on
analytics nodes (CFS, Hadoop, Spark) when you enable Kerberos
authentication
(a)ALTER KEYSPACE "system_auth" WITH REPLICATION = {'class' : 'NetworkTopologyStrategy', 'dc1' : 3, 'dc2' : 2};
(b)ALTER KEYSPACE "dse_security" WITH REPLICATION = {'class' : 'NetworkTopologyStrategy', 'dc1' : 3, 'dc2' : 2};