Jira - The #1 software development tool used by agile teams. Jira Software is built for every member of your software team to plan, track, and release great software.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Redmine - Flexible project management web application
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.
Mantis Bug Tracker - Mantis Bug Tracker is a free and open source, web-based bug tracking system.
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.