"health()"

    $response = $e->cluster->health(
        index   => 'index' | \@indices  # optional
    );

The "health()" method is used to retrieve information about the cluster health, returning "red", "yellow" or "green" to indicate the state of the cluster, indices or shards.

Query string parameters: "error_trace", "human", "level", "local", "master_timeout", "timeout", "wait_for_active_shards", "wait_for_events", "wait_for_no_relocating_shards", "wait_for_nodes", "wait_for_status"

See the cluster health docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-health.html> for more information.

"stats()"

    $response = $e->cluster->stats(
        node_id => 'node' | \@nodes     # optional
    );

Returns high-level cluster stats, optionally limited to the listed nodes.

Query string parameters: "error_trace", "flat_settings", "human", "timeout"

See the cluster stats docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-stats.html> for more information.

"get_settings()"

    $response = $e->cluster->get_settings()

The "get_settings()" method is used to retrieve cluster-wide settings that have been set with the "put_settings()" method.

Query string parameters: "error_trace", "flat_settings", "human", "include_defaults", "master_timeout", "timeout"

See the cluster settings docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-update-settings.html> for more information.

"put_settings()"

    $response = $e->cluster->put_settings( %settings );

The "put_settings()" method is used to set cluster-wide settings, either transiently (which don't survive restarts) or permanently (which do survive restarts).

For instance:

    $response = $e->cluster->put_settings(
        body => {
            transient => { "discovery.zen.minimum_master_nodes" => 5 }
        }
    );

Query string parameters: "error_trace", "flat_settings", "human"

See the cluster settings docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-update-settings.html> for more information.

"state()"

    $response = $e->cluster->state(
        metric => $metric | \@metrics   # optional
        index  => $index  | \@indices   # optional
    );

The "state()" method returns the current cluster state from the master node, or from the responding node if "local" is set to "true".

It returns all metrics by default, but these can be limited to any of: "_all", "blocks", "metadata", "nodes", "routing_table"

Metrics for indices can be limited to particular indices with the "index" parameter.

Query string parameters: "allow_no_indices", "error_trace", "expand_wildcards", "flat_settings", "human", "ignore_unavailable", "local", "master_timeout"

See the cluster state docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-state.html> for more information.

"allocation_explain()"

    $response = $e->cluster->allocation_explain(
        body => { ... shard selectors ...}  # optional
    );

Returns information about why a shard is allocated or unallocated or why.

Query string parameters: "error_trace", "human", "include_disk_info", "include_yes_decisions"

See the cluster allocation explain docs <https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-allocation-explain.html> for more information.

"pending_tasks()"

    $response = $e->cluster->pending_tasks();

Returns a list of cluster-level tasks still pending on the master node.

Query string parameters: "error_trace", "human", "local", "master_timeout"

See the pending tasks docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-pending.html> for more information.

"reroute()"

    $e->cluster->reroute(
        body => { commands }
    );

The "reroute()" method is used to manually reallocate shards from one node to another. The "body" should contain the "commands" indicating which changes should be made. For instance:

    $e->cluster->reroute(
        body => {
            commands => [
                { move => {
                    index     => 'test',
                    shard     => 0,
                    from_node => 'node_1',
                    to_node   => 'node_2
                }},
                { allocate => {
                    index     => 'test',
                    shard     => 1,
                    node      => 'node_3'
                }}
            ]
        }
    );

Query string parameters: "dry_run", "error_trace", "explain", "human", "master_timeout", "metric", "retry_failed", "timeout"

See the reroute docs <http://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-reroute.html> for more information.

"remote_info()"

    $response = $e->cluster->remote_info();

The "remote_info()" API retrieves all of the configured remote cluster information.

Query string parameters: "error_trace", "human"

See the remote_info docs <https://www.elastic.co/guide/en/elasticsearch/reference/current/cluster-remote-info.html> for more information.