diff --git a/docs/reference/modules/discovery/discovery-settings.asciidoc b/docs/reference/modules/discovery/discovery-settings.asciidoc index 3386fd66b49..aaa39c9db62 100644 --- a/docs/reference/modules/discovery/discovery-settings.asciidoc +++ b/docs/reference/modules/discovery/discovery-settings.asciidoc @@ -25,6 +25,23 @@ Discovery and cluster formation are affected by the following settings: compatibility. Support for the old name will be removed in a future version. +`cluster.initial_master_nodes`:: + + Sets a list of the <> or transport addresses of the + initial set of master-eligible nodes in a brand-new cluster. By default + this list is empty, meaning that this node expects to join a cluster that + has already been bootstrapped. See <>. + +[float] +==== Expert settings + +Discovery and cluster formation are also affected by the following +_expert-level_ settings, although it is not recommended to change any of these +from their default values. + +[WARNING] If you adjust these settings then your cluster may not form correctly +or may become unstable or intolerant of certain failures. + `discovery.cluster_formation_warning_timeout`:: Sets how long a node will try to form a cluster before logging a warning @@ -49,6 +66,7 @@ Discovery and cluster formation are affected by the following settings: handshake. Defaults to `1s`. `discovery.request_peers_timeout`:: + Sets how long a node will wait after asking its peers again before considering the request to have failed. Defaults to `3s`. @@ -83,73 +101,78 @@ Discovery and cluster formation are affected by the following settings: Sets the amount to increase the upper bound on the wait before an election on each election failure. Note that this is _linear_ backoff. This defaults - to `100ms` + to `100ms`. Changing this setting from the default may cause your cluster + to fail to elect a master node. `cluster.election.duration`:: - Sets how long each election is allowed to take before a node considers it to - have failed and schedules a retry. This defaults to `500ms`. + Sets how long each election is allowed to take before a node considers it + to have failed and schedules a retry. This defaults to `500ms`. Changing + this setting from the default may cause your cluster to fail to elect a + master node. `cluster.election.initial_timeout`:: Sets the upper bound on how long a node will wait initially, or after the elected master fails, before attempting its first election. This defaults - to `100ms`. - + to `100ms`. Changing this setting from the default may cause your cluster + to fail to elect a master node. `cluster.election.max_timeout`:: Sets the maximum upper bound on how long a node will wait before attempting an first election, so that an network partition that lasts for a long time - does not result in excessively sparse elections. This defaults to `10s` + does not result in excessively sparse elections. This defaults to `10s`. + Changing this setting from the default may cause your cluster to fail to + elect a master node. [[fault-detection-settings]]`cluster.fault_detection.follower_check.interval`:: Sets how long the elected master waits between follower checks to each - other node in the cluster. Defaults to `1s`. + other node in the cluster. Defaults to `1s`. Changing this setting from the + default may cause your cluster to become unstable. `cluster.fault_detection.follower_check.timeout`:: Sets how long the elected master waits for a response to a follower check - before considering it to have failed. Defaults to `10s`. + before considering it to have failed. Defaults to `10s`. Changing this + setting from the default may cause your cluster to become unstable. `cluster.fault_detection.follower_check.retry_count`:: Sets how many consecutive follower check failures must occur to each node before the elected master considers that node to be faulty and removes it - from the cluster. Defaults to `3`. + from the cluster. Defaults to `3`. Changing this setting from the default + may cause your cluster to become unstable. `cluster.fault_detection.leader_check.interval`:: Sets how long each node waits between checks of the elected master. - Defaults to `1s`. + Defaults to `1s`. Changing this setting from the default may cause your + cluster to become unstable. `cluster.fault_detection.leader_check.timeout`:: Sets how long each node waits for a response to a leader check from the elected master before considering it to have failed. Defaults to `10s`. + Changing this setting from the default may cause your cluster to become + unstable. `cluster.fault_detection.leader_check.retry_count`:: Sets how many consecutive leader check failures must occur before a node considers the elected master to be faulty and attempts to find or elect a - new master. Defaults to `3`. + new master. Defaults to `3`. Changing this setting from the default may + cause your cluster to become unstable. `cluster.follower_lag.timeout`:: Sets how long the master node waits to receive acknowledgements for cluster - state updates from lagging nodes. The default value is `90s`. If a node does - not successfully apply the cluster state update within this period of time, - it is considered to have failed and is removed from the cluster. See + state updates from lagging nodes. The default value is `90s`. If a node + does not successfully apply the cluster state update within this period of + time, it is considered to have failed and is removed from the cluster. See <>. -`cluster.initial_master_nodes`:: - - Sets a list of the <> or transport addresses of the - initial set of master-eligible nodes in a brand-new cluster. By default - this list is empty, meaning that this node expects to join a cluster that - has already been bootstrapped. See <>. - `cluster.join.timeout`:: Sets how long a node will wait after sending a request to join a cluster @@ -165,8 +188,7 @@ Discovery and cluster formation are affected by the following settings: `cluster.publish.timeout`:: Sets how long the master node waits for each cluster state update to be - completely published to all nodes. The default value is `30s`. If this - period of time elapses, the cluster state change is rejected. See + completely published to all nodes. The default value is `30s`. See <>. [[no-master-block]]`cluster.no_master_block`::