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Engineering notes from operating open infrastructure: the failures, design decisions, and upstream work that make open infrastructure better.
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Elasticity is a feature you pay for. It is worth it for a viral spike, but wasted on flat baseline load. A framework for measuring your peak-to-median ratio and placing workloads where they belong.
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Learn how to right-size cloud infrastructure using workload data, CPU, memory, storage, networking, peak demand, capacity planning, and growth.
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Learn the differences between data residency, data sovereignty, and data localization, and how they affect cloud compliance and private cloud strategy.
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Nodepool enables Zuul to support a multi-cloud environment by launching single-use test nodes from the most compatible node resource available.
Zuul is built for testing! The flexible configurations that Zuul provides are key differentiating factors of the tool against other generic automation tools. Zuul provides test environment provisioning via Nodepool. Nodepool is a part of a comprehensive suite of tools for testing which includes Zuul itself, each performing a specific function in the job execution workflow.
Nodepool is a system for managing test node resources. Nodepool itself has two components which run as daemons, Nodepool-builder and Nodepool-launcher. Here we are covering the actions of the launcher daemons and how it works with Zuul.
In the given context, Nodepool acts as a companion pool manager, used for clean and reproducible nodes to execute Zuul jobs. Nodepool retrieves and launches single-use test nodes upon Zuul's request. It has access to nodes from different cloud providers and also manages pre-defined and pre-existing nodes. Therefore, Zuul is not limited to only your infrastructure provider and is compatible with a wider range via Nodepool. Nodepool supports the following resources:
As mentioned earlier, this support is made available for Zuul users when Nodepool launches a fresh node for every new test. Therefore, AWS Zuul is just one of many other deployment options available to Zuul users. To better understand how Zuul and Nodepool work together, their functions can be broken down into the following steps:
This is an example of a standard workflow when a single job is to be run. In the case of multiple jobs, the corresponding number of nodes is requested from Nodepool. A single job can also be classified as a multi-nodes job if more than one node is required for the execution process and subsequently the required amount of resource is requested. Since fresh nodes are requested for each job execution, it reduces job erraticness and ensures a robust workspace.
On the other hand, Nodepool-builder daemon is used for building and uploading images to providers. The diskimage-builder is responsible for building the underlying images. Also, Nodepool is able to build cloud instances from these images created.
The configuration file for Nodepool also follows the YAML syntax, making it just as well integrated with Ansible. Due to this, the multi-cloud merging process is efficiently automated. This further ensures
effective coordination between workloads and the management of hybrid workflows.
If Zuul is something you need or are interested in, check out our Managed Zuul solution offering and contact us for any queries!
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