This is a re-edit of my previous post "Indexing and searching Weblogic logs using Logstash and Graylog2". Meanwhile our setup has settled to use Kibana instead of the Graylog2 frontend. This Howto is meant to be a complete installation guide for "The Elasticsearch ELK stack" and using it to index tons of Weblogic server and application logs, from DEV over UA to the Production environment.
My current project is to take our Weblogic monitoring setup from parsing gc logs in Splunk up to the next level. For other things metrics we do use Graphite already. Graphite is an awesome app for graphing any sort of metrics. You just need to get them in there somehow. Some days ago I stumbled over an outstanding piece of software written by Dimo Velev: metrics-sampler.
Update 2013/10: we decided to replace Graylog2 with Kibana3 completely. The article below is just for reference, the logstash config is outdated since logstash 1.2 and the setup as described below is suboptimal anyway. I'll post a new article shortly.
Update 2014/02: Finally, the new guide is here: Indexing and searching Weblogic logs using Logstash, Elasticsearch and Kibana.