Configure Fluentd Services to Write to Elasticsearch Nodes on the Same Rack

On clusters with high-density racks, ensure you have at least one Elasticsearch server per rack and configure each Fluentd service to write to Elasticsearch nodes that run on the same rack as the Fluentd service. This configuration minimizes the impact of log aggregation on other processes that run on the cluster and in particular, minimizes the amount of backbone bandwidth used by the log aggregation.

Complete the following steps on each node that runs the Fluentd service.

  1. Open the /opt/mapr/fluentd/fluentd-<version>/etc/fluentd/es_config.conf file.
  2. Edit the hosts property to only include Elasticsearch nodes that are on the same rack as the Fluentd service.
    Example:
    hosts qa-node90:9200,qa-node91.qa.lab:9200,qa-node92.qa.lab:9200
  3. Restart Fluentd.
    maprcli node services -name fluentd -nodes <space separated list of fluentd nodes> -action restart
Warning: Changes to the es_config.conf files are overridden by configure.sh. Therefore, you will need reconfigure the hosts property in the es_config.conf file after configure.sh is run on Fluentd nodes.