Despite overall Elasticsearch stability, it is still possible for a cluster to get into a "red" state. One of the reasons for that to happen is if an index becomes corrupt. This can be caused by an abrupt loss of power, hardware failure or—more commonly—running out of disk space. In this post we'll discuss how to bring the cluster to a healthy state with minimal or no data loss in such situation.
CrateDB offers Standard-SQL, real-time queries and document support (JSON) in a simple, horizontal way to scale.
This talk will teach you about Elasticsearch and Lucene's architecture.
The key data structure in search is the powerful inverted index, which is actually simple to understand. We start there, then ascend through abstraction layers to get an overview of how a distributed search cluster processes searches and changes
Centralize all your log messages
- Collect terabytes of log messages
- Process in real-time
- Search and analyze in seconds
Graphite does two things:
1) Store numeric time-series data
2) Render graphs of this data on demand
What Graphite does not do is collect data for you, however there are some tools out there that know how to send data to graphite. Even though it often requires a little code, sending data to Graphite is very simple.
Kibana is an open source (Apache Licensed), browser based analytics and search dashboard for ElasticSearch. Kibana is a snap to setup and start using. Written entirely in HTML and Javascript it requires only a plain webserver, Kibana requires no fancy server side components. Kibana strives to be easy to get started with, while also being flexible and powerful, just like Elasticsearch.
logstash is a tool for managing events and logs. You can use it to collect logs, parse them, and store them for later use (like, for searching). Speaking of searching, logstash comes with a web interface for searching and drilling into all of your logs.
It is fully free and fully open source. The license is Apache 2.0, meaning you are pretty much free to use it however you want in whatever way.
logstash is now a part of the Elasticsearch family! This allows us to build better software much faster as well as offering production support
By combining the massively popular Elasticsearch, Logstash and Kibana we have created an end-to-end stack that delivers actionable insights in real-time from almost any type of structured and unstructured data source. Built and supported by the engineers behind each of these open source products, the Elasticsearch ELK stack makes searching and analyzing data easier than ever before.