Kubernetes Namespaces: Roles, Development Landscapes, and Customer Partitioning

- Admin role: This role has admin access to all Kubernetes clusters. Admins can create/delete clusters and add/remove nodes to scale the clusters. This role will be responsible for patching, securing and maintaining the clusters. As well as implementing Quotas between the different entities in the organization. The Kubernetes Admin is responsible for implementing the namespaces strategy defined by the Designer/Architect.  These two roles and the actual developers using the clusters will also receive support and feedback from the enterprise security and network teams on issues such as security isolation requirements and how namespaces fit this model, or assistance with networking subnets and load-balancers setup. Anti-patterns 1. Isolated Kubernetes usage “Islands” without centralized control: Without the initial investment in establishing a centralized control structure around Kubernetes management there is a risk of ending with a “mushroom farm” topology i.e. no defined size/shape/structure of clusters within the org. The result is a difficult to manage, higher risk and elevated cost due to underutilization of resources. 2. Old-world IT controls choking usage and innovation: A common tendency is to try and transpose existing on-premises controls/procedures onto new dynamic frameworks .This results in weighing down the agile nature of these frameworks and nullifying the benefits of rapid dynamic deployments. 3. Omni-cluster: Delaying the effort of creating the structure/mechanism for namespace management can result in one large omni-cluster that is hard to peel back into smaller usage groups.  **Use-case #2: Using Namespaces to partition development landscapes** Software development teams customarily partition their development pipelines into discrete units. These units take various forms and use various labels but will tend to result in a discrete dev environment, a testing|QA environment, possibly a staging environment and finally a production environment. The resulting layouts are ideally suited to Kubernetes Namespaces. Each environment or stage in the pipeline becomes a unique namespace. The above works well as each namespace can be templated and mirrored to the next subsequent environment in the dev cycle, e.g. dev-\>qa-\>prod. The fact that each namespace is logically discrete allows the development teams to work within an isolated “development” namespace. DevOps (The closest role at Google is called [Site Reliability Engineering](https://landing.google.com/sre/interview/ben-treynor.html) “SRE”)  will be responsible for migrating code through the pipelines and ensuring that appropriate teams are assigned to each environment. Ultimately, DevOps is solely responsible for the final, production environment where the solution is delivered to the end-users. A major benefit of applying namespaces to the development cycle is that the naming of software components (e.g. micro-services/endpoints) can be maintained without collision across the different environments. This is due to the isolation of the Kubernetes namespaces, e.g. serviceX in dev would be referred to as such across all the other namespaces; but, if necessary, could be uniquely referenced using its full qualified name serviceX.development.mycluster.com in the development namespace of mycluster.com. Anti-patterns 1. Abusing the namespace benefit resulting in unnecessary environments in the development pipeline. So; if you don’t do staging deployments, don’t create a “staging” namespace. 2. Overcrowding namespaces e.g. having all your development projects in one huge “development” namespace. Since namespaces attempt to partition, use these to partition by your projects as well. Since Namespaces are flat, you may wish something similar to: projectA-dev, projectA-prod as projectA’s namespaces. **Use-case #3: Partitioning of your Customers** If you are, for example, a consulting company that wishes to manage separate applications for each of your customers, the partitioning provided by Namespaces aligns well. You could create a separate Namespace for each customer, customer project or customer business unit to keep these distinct while not needing to worry about reusing the same names for resources across projects.

This section discusses the role of the Kubernetes Admin in implementing the namespace strategy, highlighting the importance of support and feedback from security and network teams. It outlines anti-patterns such as isolated Kubernetes islands, rigid IT controls hindering innovation, and the creation of an unmanageable 'omni-cluster'. It then explores using namespaces to partition development landscapes into discrete environments like dev, QA, and production, enabling teams to work in isolated spaces and maintain consistent naming conventions. Finally, it suggests using namespaces to partition customers, where each customer, project, or business unit gets its own namespace for better resource management and isolation.