Assimilation System Management Suite
The Assimilation Suite discovers systems, services, network connections, configuration and dependencies, IP and MAC addresses. This all goes into a continually updated graph-based configuration management database (CMDB). This is then compared and scored against best practices, services and servers are monitored - all with near-zero configuration - in a way that scales to hundreds of thousands of servers. It also provides visualization tools, APIs for sending alerts to humans and other systems, and a variety of canned reports (queries) to aid in securing and managing systems, hooking into ChatOps, and creating plans for triaging your security issues
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Berkshelf
A cookbook source structure manager for Chef, similar to Bundler for Ruby. Each Chef cookbook can be structured as an individual entity and can be pulled into your main Chef workflows.
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FastForward
Flexible operating-system event and metric forwarding agent. Receives input and forwards output using plugins.
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GitLab
GitLab is an open-source, fully featured git web frontend developed using Ruby on Rails. You can host this in your own server, create projects, repositories and teams, manage fine grained access permissions, add wikis, collaborate, raise and merge pull requests, and do much more through the web! (Note: GitLab acquired Gitorious, another open source git management system, in March 2015)
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Graphite
Graphite is a visualization tool for statistics configured from various sources. You can create customizable reports and dashboards, and it is one of the preferred backends for Statsd
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Instrumental
Instrumental is a real-time, high-scale application and server monitoring tool with intelligent alerts, a powerful query language, and free development accounts.
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Librarian-Puppet
Librarian-Puppet is a source structure and dependency manager for Puppet modules, similar to bundler for Ruby. Each Puppet module can be managed as a separate source repository with individual versioning, and can then be pulled into your Puppetfile.
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Monit
An open source utility for managing and monitoring processes, programs, files, directories and filesystems
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Opskeleton
Bootstrap a DevOps infrastructure with some opinionated defaults (vagrant, puppet, librarian-puppet, git, etc), standard development guidelines, etc. Makes it very quick to get a DevOps team up and running
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Review Board
Review Board is a feature packed code review tool for multiple SCM systems (like git, bzr, cvs, subversion, etc).
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Supervisor
Supervisor can manage application processes. It can start and stop a group of processes, restart processes if any of them terminate (keep-alive), start multiple instances of the same process (process pooling), automatically manage PID files, and much more! Very useful if you need to manage multiple processes for your application.
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