Cassandra Documentation

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cassandra-topologies.properties file ================================

The PropertyFileSnitch snitch option uses the cassandra-topologies.properties configuration file to determine which datacenters and racks cluster nodes belong to. If other snitches are used, the :ref:cassandra_rackdc must be used. The snitch determines network topology (proximity by rack and datacenter) so that requests are routed efficiently and allows the database to distribute replicas evenly.

Include every node in the cluster in the properties file, defining your datacenter names as in the keyspace definition. The datacenter and rack names are case-sensitive.

The cassandra-topologies.properties file must be copied identically to every node in the cluster.

Example

This example uses three datacenters:

# datacenter One

175.56.12.105=DC1:RAC1
175.50.13.200=DC1:RAC1
175.54.35.197=DC1:RAC1

120.53.24.101=DC1:RAC2
120.55.16.200=DC1:RAC2
120.57.102.103=DC1:RAC2

# datacenter Two

110.56.12.120=DC2:RAC1
110.50.13.201=DC2:RAC1
110.54.35.184=DC2:RAC1

50.33.23.120=DC2:RAC2
50.45.14.220=DC2:RAC2
50.17.10.203=DC2:RAC2

# datacenter Three

172.106.12.120=DC3:RAC1
172.106.12.121=DC3:RAC1
172.106.12.122=DC3:RAC1

# default for unknown nodes
default =DC3:RAC1