Add k8s/namespace doc

docs/tech/cheats/Kubernetes/kubectl.md

@@ -13,7 +13,7 @@ import TabItem from '@theme/TabItem';
 Cheat sheet for kubectl commands.
 
 :::info
-This page was automatically generated from a navi cheat file available at [**difranca/navi-cheats**](https://github.com/difranca/navi-cheats).<br />
+This page was automatically generated from a navi cheat file available at [**difranca/navi-cheats**](https://github.com/difranca/navi-cheats).<br/>
 **Navi** is an interactive cheatsheet tool for the command-line. To learn more about it, visit [**denisidoro/navi**](https://github.com/denisidoro/navi).
 :::
 

docs/tech/cloud/kubernetes/index.md

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+---
+keywords: [kubernetes, k8s, kubectl]
+slug: /cloud/kubernetes
+title: Kubernetes | Cloud | Tech-Notes
+sidebar_label: Kubernetes
+---
+
+# Kubernetes
+
+<br/>
+
+<div style={{textAlign: 'center'}}>
+
+<img width="200" height="200" alt="logo" src="/img/cloud/kubernetes.png"/>
+
+_Kubernetes is an open-source system for automating deployment, scaling, and management of containerized applications._
+
+</div>
+
+:::note More Information
+
+- https://www.kubernetes.io
+
+:::
+
+<br/>
+
+## Index
+
+import DocCardList from '@theme/DocCardList';
+import {useCurrentSidebarCategory} from '@docusaurus/theme-common';
+
+<DocCardList items={useCurrentSidebarCategory().items}/>

docs/tech/cloud/kubernetes/namespace.md

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+---
+keywords: [kubernetes, k8s, kubectl, namespace]
+title: Namespaces | Kubernetes | Cloud | Tech-Notes
+sidebar_label: Namespaces
+---
+
+# Namespaces
+
+Namespaces provides a mechanism for isolating groups of resources within a single cluster.
+
+- Names of resources need to be unique within a namespace
+- Namespace-based scoping is applicable only for namespaced objects and not for cluster-wide objects
+
+:::note More Information
+
+- https://kubernetes.io/docs/concepts/overview/working-with-objects/namespaces/
+
+:::
+
+<br/>
+
+## Namespaces Stuck in Terminating
+
+When deleting a namespace in Kubernetes, the namespace may remain stuck in terminating status.
+
+```bash
+$ kubectl get ns
+
+NAME               STATUS        AGE
+default            Active        2d
+kube-public        Active        2d
+kube-system        Active        2d
+my-namespace       Terminating   7m 
+```
+
+### Solution
+
+1. Get the namespace manifest
+
+```bash
+$ kubectl get ns my-namespace -o yaml > namespace.yaml 
+```
+
+2. Edit the manifest file and remove all finalizers 
+
+```yaml
+apiVersion: v1
+kind: Namespace
+metadata:
+  name: my-namespace
+spec:
+  finalizers:
+status:
+  phase: Terminating
+```
+
+3. Start kubectl proxy
+
+```bash
+$ kubectl proxy
+
+Starting to serve on 127.0.0.1:8001
+```
+
+4. Call namespace finalize API:
+
+```bash
+$ curl -H "Content-Type: application/yaml" -X PUT --data-binary @namespace.yaml http://127.0.0.1:8001/api/v1/namespaces/my-namespace/finalize 
+```
+
+5. Confirm if namespace was deleted
+
+```bash
+$ kubectl get ns
+
+NAME               STATUS        AGE
+default            Active        2d
+kube-public        Active        2d
+kube-system        Active        2d
+``