Monitoring

General Monitoring

• http://www.nagios.org/
• http://munin-monitoring.org/
• http://www.zenoss.com/
• http://www.splunk.com
• http://www.pagerduty.com (Send SMS or Phone call notifications from almost any monitoring software)
• https://scoutapp.com
• http://www.logicmonitor.com
• http://www.compuware.com/application-performance-management
• http://www.monitis.com
• https://qloudstat.com (Analytics & monitoring for access logs in Amazon S3, Amazon CloudFront, Google Cloud Storage and Rackspace CloudFiles. Plotting hits in a chart, timeline, table or geographical map)

Open Source

• https://github.com/graphite-project/graphite-web (see also https://github.com/graphite-project/whisper and https://github.com/graphite-project/carbon)

SASS

• http://newrelic.com/

Network Monitoring

• http://www.paessler.com/