Consul
Consul makes it simple for services to register themselves and to discover other services via a DNS or HTTP interface. Register external services such as SaaS providers as well
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SaltStack
Salt is a powerful and different approach to infrastructure management, by focusing on high speed communications between large number of systems, and can perform orchestration, remote code execution and much more.
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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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Vaurien
A Chaos Monkey for TCP, it randomly disconnects or stalls TCP connections in your application to test application tolerance and high availability. Makes sure you correctly handle these unexpected events
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