Prometheus alert rules for Elasticsearch

Assuming https://github.com/vvanholl/elasticsearch-prometheus-exporter/ plugin is installed on every ES node to enable scraping metrics by Prometheus server.

Verify rules file

Use promtool utility (it is part of Prometheus installation).

promtool check rules ./logging_elasticsearch.rules.yaml

This ^^ check is part of Travis integration.

Deploy rules into Prometheus server

The following is a quick & dirty description how to deploy rules file into Prometheus server. For more information consult Prometheus documentation.

# Assuming the default Prometheus installation
$ pwd
/etc/prometheus

wget https://raw.githubusercontent.com/lukas-vlcek/prometheus-elasticsearch-rules/master/logging_elasticsearch.rules.yaml

$ ls 
logging_elasticsearch.rules.yaml
prometheus.yml

# Add rules file into Prometheus configuration file
$ vi prometheus.yml

## Add the following to the file:
rule_files:
  - logging_elasticsearch.rules.yaml

# Restart Prometheus server to make it reload configuration.
kill -HUP `pgrep prometheus`

Navigate to the Prometheus WEB UI and go to "Alerts" tab.