OTUS SIEM!

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.

Open Web Analytics - Web Analytics – Open Source Web Analytics Framework

Graylog is an open source syslog implementation that stores your logs in Elasticsearch. It consists of a server and web interface written in Java that accepts your syslog messages via TCP or UDP (or GELF messages) and stores it in the database.

Logmatic.io is an Operations Data Platform for Log and Machine events. We help companies improve their software and business performance by leveraging their machine data.

Grafana provides a powerful and elegant way to create, explore, and share dashboards and data with your team and the world.

Splunk is software that provides unique visibility across your entire IT infrastructure from one place in real time. Only Splunk enables you to search, report, monitor and analyze streaming and historical data from any source. Troubleshoot application problems and investigate security incidents in minutes instead of hours or days, monitor to avoid service degradation or outages, deliver compliance at lower cost and gain new business insights from your IT data.

Hosted log management for servers, apps, and cloud services. Papertrail aggregates syslog, Text log files, Apache, MySQL, cloud hosting, Ruby on Rails, Windows events, Tomcat, Heroku apps, and routers & firewalls.

Prometheus is an open-source systems monitoring and alerting toolkit originally built at SoundCloud. Since its inception in 2012, many companies and organizations have adopted Prometheus, and the project has a very active developer and user community. It is now a standalone open source project and maintained independently of any company.

Airbrake collects errors generated by other applications, and aggregates the results for review.

logsniffer is a sophisticated open source web tool for viewing, monitoring and analyzing log data - smarter and easier.It provides an awesome and intuitive web log viewer to keep an eye on all your logs - in one place and in real-time. It was never easier to scroll and search through gigs of logs using simply a web browser.Monitor your infrastructure by sniffing logs for events of your interest. logsniffer provides powerful scan routines and alerting to several channels.Download and run logsniffer on premise. It will take only minutes and keep logs secret. »

Nagios Log Server is a powerful enterprise-class log monitoring and management application that allows organizations to quickly and easily view, sort, and configure logs from any source on any given network. Log Server is designed to analyze, collect, and store log data based on custom specifications, and provide users with extended insight into the data on their network's infrastructure.

App Enlight- provides a helpful interface to let you and your team save time spent on debugging and reproducing errors and performance problems from a production environment.

Loggly is a cloud-based log management service built on top of a powerful search engine. With Loggly, you can collect logs from your servers then quickly search them with an intuitive user interface. We make looking at logs fun again!

Logentries is a cloud-based service for log collection, correlation, and presentation in a meaningful way. Logentries is reliable and extremely scalable service providing real-time alerts, regular-expression search, graphing and visualization for thousands of users.