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The "FAQ" page has been changed by TylerHobbs: http://wiki.apache.org/cassandra/FAQ?action=diff&rev1=152&rev2=153 Comment: Remove very old notes about autobootstrap behavior <<Anchor(ports)>> == What ports does Cassandra use? == - By default, Cassandra uses 7000 for cluster communication (7001 is SSL is enabled), 9160 for clients (Thrift), and 7199 for [[JmxInterface|JMX]]. The internode communication and Thrift ports are configurable in cassandra.yaml, and the JMX port is configurable in cassandra-env.sh (through JVM options). All ports are TCP. See also RunningCassandra. + By default, Cassandra uses 7000 for cluster communication (7001 if SSL is enabled), 9160 for clients (Thrift), and 7199 for [[JmxInterface|JMX]]. The internode communication and Thrift ports are configurable in cassandra.yaml, and the JMX port is configurable in cassandra-env.sh (through JVM options). All ports are TCP. See also RunningCassandra. <<Anchor(slows_down_after_lotso_inserts)>> @@ -73, +73 @@ <<Anchor(existing_data_when_adding_new_nodes)>> == What happens to existing data in my cluster when I add new nodes? == - Starting a new node with the -b [bootstrap] option will cause it to contact other nodes in the cluster to copy the right data to itself. + When a new nodes joins a cluster, it will automatically contact the other nodes in the cluster and copy the right data to itself. + In general, you should set the 'initial_token' config option in cassandra.yaml before starting a new node. Otherwise, a suboptimal token may be selected automatically, leading to an unbalanced ring. See [[Operations#Token_selection|token selection]] in the operations wiki. - In Cassandra 0.5 and above, there is an "AutoBootStrap" option in the config file. When enabled, using the "-b" options is unnecessary, because new nodes will automatically bootstrap themselves when they start up for the first time. Even with AutoBootstrap it is recommended that you always specify the InitialToken because the picking of an initial token will almost certainly result in an unbalanced ring. If you are building the initial cluster you certainly don't want to leave InitialToken blank. Pick the tokens such that the ring will be balanced afterward and explicitly set them on each node. See [[Operations#Token_selection|token selection]] in the operations wiki. - - Unless you know precisely what you're doing and are aware of how the Cassandra internals work you should never introduce a new empty node to your cluster and have autoboostrap disabled. In version 0.7 under write load it will cause writes to be sent to the new node before the schema arrives from another member of the cluster. This would also indicate to clients that the new node is responsible for servicing reads for data that it definitely doesn't have. - - In Cassandra 0.4 and below, it is recommended that you manually specify a value for "InitialToken" in the config file of a new node. <<Anchor(node_clients_connect_to)>>
