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Deflake test-api job, currently failing at around 7.6% (44 out of 578 workflows), by ensuring that test nomad agent use a small dedicated port range that doesn't conflict with the kernel ephemeral range. The failures are disproportionatly related to port allocation, where a nomad agent fails to start when the http port is already bound to another process. The failures are intermitent and aren't specific to any test in particular. The following is a representative failure: https://app.circleci.com/pipelines/github/hashicorp/nomad/13995/workflows/6cf6eb38-f93c-46f8-8aa0-f61e62fe7694/jobs/128169 . Upon investigation, the issue seems to be that the api freeport library picks a port block within 10,000-14,500, but that overlaps with the kernel ephemeral range 32,769-60,999! So, freeport may allocate a free port to the nomad agent, just to be used by another process before the nomad agent starts! This happened for example in https://app.circleci.com/pipelines/github/hashicorp/nomad/14111/workflows/e1fcd7ff-f0e0-4796-8719-f57f510b1ffa/jobs/129684 . `freeport` allocated port 41662 to serf, but `google_accounts` raced to use it to connect to the CirleCI vm metadata service. We avoid such races by using a dedicated port range that's disjoint from the kernel ephemeral port range.
Nomad 
Nomad is a simple and flexible workload orchestrator to deploy and manage containers (docker, podman), non-containerized applications (executable, Java), and virtual machines (qemu) across on-prem and clouds at scale.
Nomad is supported on Linux, Windows, and macOS. A commercial version of Nomad, Nomad Enterprise, is also available.
- Website: https://nomadproject.io
- Tutorials: HashiCorp Learn
- Forum: Discuss
- Mailing List: Google Groups
- Gitter: hashicorp-nomad
Nomad provides several key features:
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Deploy Containers and Legacy Applications: Nomad’s flexibility as an orchestrator enables an organization to run containers, legacy, and batch applications together on the same infrastructure. Nomad brings core orchestration benefits to legacy applications without needing to containerize via pluggable task drivers.
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Simple & Reliable: Nomad runs as a single binary and is entirely self contained - combining resource management and scheduling into a single system. Nomad does not require any external services for storage or coordination. Nomad automatically handles application, node, and driver failures. Nomad is distributed and resilient, using leader election and state replication to provide high availability in the event of failures.
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Device Plugins & GPU Support: Nomad offers built-in support for GPU workloads such as machine learning (ML) and artificial intelligence (AI). Nomad uses device plugins to automatically detect and utilize resources from hardware devices such as GPU, FPGAs, and TPUs.
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Federation for Multi-Region, Multi-Cloud: Nomad was designed to support infrastructure at a global scale. Nomad supports federation out-of-the-box and can deploy applications across multiple regions and clouds.
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Proven Scalability: Nomad is optimistically concurrent, which increases throughput and reduces latency for workloads. Nomad has been proven to scale to clusters of 10K+ nodes in real-world production environments.
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HashiCorp Ecosystem: Nomad integrates seamlessly with Terraform, Consul, Vault for provisioning, service discovery, and secrets management.
Quick Start
Testing
See Learn: Getting Started for instructions on setting up a local Nomad cluster for non-production use.
Optionally, find Terraform manifests for bringing up a development Nomad cluster on a public cloud in the terraform directory.
Production
See Learn: Nomad Reference Architecture for recommended practices and a reference architecture for production deployments.
Documentation
Full, comprehensive documentation is available on the Nomad website: https://www.nomadproject.io/docs
Guides are available on HashiCorp Learn.
Contributing
See the contributing directory for more developer documentation.