3.3. Configuring Clustering¶
3.3.1. Cluster Options¶
Sets the default number of shards for newly created databases. The default value,
8, splits a database into 8 separate partitions.
[cluster] q = 8
For systems with lots of small, infrequently accessed databases, or for servers with fewer CPU cores, consider reducing this value to
The value of
qcan also be overridden on a per-DB basis, at DB creation time.
Sets the number of replicas of each document in a cluster. CouchDB will only place one replica per node in a cluster. When set up through the Cluster Setup Wizard, a standalone single node will have
n = 1, a two node cluster will have
n = 2, and any larger cluster will have
n = 3. It is recommended not to set
[cluster] n = 3
Use of this option will override the
noption for replica cardinality. Use with care.
Sets the cluster-wide replica placement policy when creating new databases. The value must be a comma-delimited list of strings of the format
zone_nameis a zone as specified in the
#is an integer indicating the number of replicas to place on nodes with a matching
This parameter is not specified by default.
[cluster] placement = metro-dc-a:2,metro-dc-b:1
An optional, comma-delimited list of node names that this node should contact in order to join a cluster. If a seedlist is configured the
_upendpoint will return a 404 until the node has successfully contacted at least one of the members of the seedlist and replicated an up-to-date copy of the
_userssystem databases.[cluster] seedlist = firstname.lastname@example.org,email@example.com