What are some alternatives?
logstash - logstash is a tool for managing events and logs.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Raygun - Raygun gives developers meaningful insights into problems affecting their applications. Discover issues - Understand the problem - Fix things faster.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Kafka - Apache Kafka is publish-subscribe messaging rethought as a distributed commit log.
Site24x7 - Site24x7 offers both free & paid website monitoring services. Monitor websites remotely and receive instant email/sms alerts if your website becomes unavailable. View uptime & performance graphs of your website monitors.