Voting configuration exclusions API

Adds or removes master-eligible nodes from the voting configuration exclusion list.

POST _cluster/voting_config_exclusions/<node_name>

DELETE _cluster/voting_config_exclusions

By default, if there are more than three master-eligible nodes in the cluster and you remove fewer than half of the master-eligible nodes in the cluster at once, the voting configuration automatically shrinks.

If you want to shrink the voting configuration to contain fewer than three nodes or to remove half or more of the master-eligible nodes in the cluster at once, you must use this API to remove departed nodes from the voting configuration manually. It adds an entry for that node in the voting configuration exclusions list. The cluster then tries to reconfigure the voting configuration to remove that node and to prevent it from returning.

If the API fails, you can safely retry it. Only a successful response guarantees that the node has been removed from the voting configuration and will not be reinstated.

The cluster.max_voting_config_exclusions setting limits the size of the voting configuration exclusion list. The default value is 10. Since voting configuration exclusions are persistent and limited in number, you must clear the voting config exclusions list once the exclusions are no longer required.

There is also a cluster.auto_shrink_voting_configuration setting, which is set to true by default. If it is set to false, you must use this API to maintain the voting configuration.

For more information, see Removing master-eligible nodes.

Add nodeId1 to the voting configuration exclusions list:

POST /_cluster/voting_config_exclusions/nodeId1

Remove all exclusions from the list:

DELETE /_cluster/voting_config_exclusions