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Restrictions are used to allow or restrict where jobs run, and are applied to both jobs and Workers. Restrictions are based on cluster names, but differ from the clusters themselves in an important way:
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Jobs and workers can belong to 1 and only 1 cluster, but can be restricted to none, 1, or several clusters |
This seems a bit hard to understand, until you remember that a job has preferential priority on a Worker whose cluster matches the job's cluster, but the job is free to run on any Worker in other clusters. The job's restriction value can be used to limit what other clusters the job could possibly run on.
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