Some references for Logstash+ElasticSearch+Kibana
These log files are still hard to use on their own. They are made by a computer for a computer and I am human trying to understand other humans. Logstash, ElasticSearch and Kibana to the rescue! Logstash is a tool for managing events and logs. You can use it to collect logs, parse them, and store them for later use (statement humbly borrowed fromhttp://logstash.net). ElasticSearch is a distributed restful search and analytics engine (yet again borrowed, but fromhttp://www.elasticsearch.org/overview/). Kibana is a GUI tool to visualize logs and time-stamped data in realtime (yet again borrowed, but from http://www.elasticsearch.org/overview/kibana/). These three tools make up a pretty good toolkit for creating some graphs and dashboards.
Read more at http://nhhagen.wordpress.com/2013/11/28/query-log-analysis-using-logstash-elasticsearch-and-kibana/