Configuring gossip settings
Using the cassandra.yaml file to configure gossip.
When a node first starts up, it looks at its cassandra.yaml configuration file to determine the name of the Cassandra cluster it belongs to; which nodes (called seeds) to contact to obtain information about the other nodes in the cluster; and other parameters for determining port and range information.
The location of the cassandra.yaml file depends on the type of
installation:
| Package installations | /etc/cassandra/cassandra.yaml |
| Tarball installations | install_location/resources/cassandra/conf/cassandra.yaml |
Procedure
In the cassandra.yaml file, set the following
parameters:
| Property | Description |
|---|---|
| cluster_name | Name of the cluster that this node is joining. Must be the same for every node in the cluster. |
| listen_address | The IP address or hostname that Cassandra binds to for connecting this node to other nodes. |
| listen_interface | Use this option instead of listen_address to specify the network interface by name, rather than address/hostname |
| (Optional) broadcast_address |
The "public" IP
address this node uses to broadcast to other nodes
outside the network or across regions in
multiple-region EC2 deployments. If this property
is commented out, the node uses the same IP
address or hostname as
listen_address. A node does not
need a separate broadcast_address
in a single-node or single-datacenter
installation, or in an EC2-based network that
supports automatic switching between private and
public communication. It is necessary to set a
separate listen_address and
broadcast_address on a node with
multiple physical network interfaces or other
topologies where not all nodes have access to
other nodes by their private IP addresses. For
specific configurations, see the instructions for
listen_address. The default
is the listen_address. |
| seed_provider | A -seeds list is comma-delimited list of hosts (IP addresses) that
gossip uses to learn the topology of the ring. Every node should have
the same list of seeds. Attention: In multiple data-center clusters, include at least one
node from each datacenter (replication group) in the seed list. Designating more than a single
seed node per datacenter is recommended for fault tolerance. Otherwise, gossip has to communicate
with another datacenter when bootstrapping a node.
Making every node a seed node is not recommended because of increased maintenance and reduced gossip performance. Gossip optimization is not critical, but it is recommended to use a small seed list (approximately three nodes per datacenter). |
| storage_port | The inter-node communication port (default is 7000). Must be the same for every node in the cluster. |
| initial_token | For legacy clusters. Set this property for single-node-per-token architecture, in which a node owns exactly one contiguous range in the ring space. |
| num_tokens | For new clusters. The number of tokens randomly assigned to this node in a cluster that uses virtual nodes (vnodes). |