fd16f80b5a
* Only error on constraints if no allocs are running When running `nomad job run <JOB>` multiple times with constraints defined, there should be no error as a result of filtering out nodes that do not/have not ever satsified the constraints. When running a systems job with constraint, any run after an initial startup returns an exit(2) and a warning about unplaced allocations due to constraints. An error that is not encountered on the initial run, though the constraint stays the same. This is because the node that satisfies the condition is already running the allocation, and the placement is ignored. Another placement is attempted, but the only node(s) left are the ones that do not satisfy the constraint. Nomad views this case (no allocations that were attempted to placed could be placed successfully) as an error, and reports it as such. In reality, no allocations should be placed or updated in this case, but it should not be treated as an error. This change uses the `ignored` placements from diffSystemAlloc to attempt to determine if the case encountered is an error (no ignored placements means that nothing is already running, and is an error), or is not one (an ignored placement means that the task is already running somewhere on a node). It does this at the point where `failedTGAlloc` is populated, so placement functionality isn't changed, just the field that populates error. There is functionality that should be preserved which (correctly) notifies a user if a job is attempted that cannot be run on any node due to the constraints filtering out all available nodes. This should still behave as expected. * Add changelog entry * Handle in-place updates for constrained system jobs * Update .changelog/25850.txt Co-authored-by: Piotr Kazmierczak <470696+pkazmierczak@users.noreply.github.com> * Remove conditionals --------- Co-authored-by: Piotr Kazmierczak <470696+pkazmierczak@users.noreply.github.com>
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://developer.hashicorp.com/nomad
- Tutorials: HashiCorp Developer
- Forum: Discuss
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 Developer: 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 Developer: Nomad Reference Architecture for recommended practices and a reference architecture for production deployments.
Documentation
Full, comprehensive documentation is available on the Nomad website: https://developer.hashicorp.com/nomad/docs
Guides are available on HashiCorp Developer.
Roadmap
A timeline of major features expected for the next release or two can be found in the Public Roadmap.
This roadmap is a best guess at any given point, and both release dates and projects in each release are subject to change. Do not take any of these items as commitments, especially ones later than one major release away.
Contributing
See the contributing directory for more developer documentation.