This is archived documentation for InfluxData product versions that are no longer maintained. For newer documentation, see the latest InfluxData documentation.
data node
A node that runs the data service.
For high availability, installations must have at least two data nodes. The number of data nodes in your cluster must be the same as your highest replication factor. Any replication factor greater than two gives you additional fault tolerance and query capacity within the cluster.
Data node sizes will depend on your needs. The Amazon EC2 m4.large or m4.xlarge are good starting points.
Related entries: data service, replication factor
data service
Stores all time series data and handles all writes and queries.
Related entries: data node
meta node
A node that runs the meta service.
For high availability, installations must have three meta nodes. Meta nodes can be very modestly sized instances like an EC2 t2.micro or even a nano. For additional fault tolerance installations may use five meta nodes; the number of meta nodes must be an odd number.
Related entries: meta service
meta service
The consistent data store that keeps state about the cluster, including which servers, databases, users, continuous queries, retention policies, subscriptions, and blocks of time exist.
Related entries: meta node
replication factor
The attribute of the retention policy that determines how many copies of the
data are stored in the cluster.
InfluxDB replicates data across N data nodes, where N is the replication
factor.
To maintain data availability for queries, the replication factor should be less than or equal to the number of data nodes in the cluster:
- Data is fully available when the replication factor is greater than the number of unavailable data nodes.
- Data may be unavailable when the replication factor is less than the number of unavailable data nodes.
Any replication factor greater than two gives you additional fault tolerance and query capacity within the cluster.