From 64af745244caa793b7522b6bcae39824a58d3581 Mon Sep 17 00:00:00 2001
From: root <pirouz.radin@yahoo.com>
Date: Sun, 29 Jun 2025 16:56:28 +0330
Subject: [PATCH] update kuber doc

---
 .../Kubernetes/components/5-hpa.md            | 67 ++++++++++++++++
 .../Kubernetes/components/6-DaemonSet.md      | 40 ++++++++++
 .../Kubernetes/node-manage.md                 | 77 ++++++++++++-------
 3 files changed, 155 insertions(+), 29 deletions(-)
 create mode 100644 Containerization & Orchestration/Kubernetes/components/5-hpa.md
 create mode 100644 Containerization & Orchestration/Kubernetes/components/6-DaemonSet.md

diff --git a/Containerization & Orchestration/Kubernetes/components/5-hpa.md b/Containerization & Orchestration/Kubernetes/components/5-hpa.md
new file mode 100644
index 0000000..ffa1844
--- /dev/null
+++ b/Containerization & Orchestration/Kubernetes/components/5-hpa.md	
@@ -0,0 +1,67 @@
+# 📈 Horizontal Pod Autoscaler (HPA)
+
+The Horizontal Pod Autoscaler automatically scales the number of pods in a deployment based on observed CPU utilization (or other select metrics).
+
+---
+
+## ⚙️ Basic Commands
+
+### 🚀 Create an HPA
+Create an HPA for a deployment, scaling based on CPU usage:
+
+```bash
+kubectl -n <namespace> autoscale deployment <deployment-name> --cpu-percent=20 --min=4 --max=10
+````
+
+### 📊 View Existing HPAs
+
+List all HPAs in a specific namespace:
+
+```bash
+kubectl get hpa -n <namespace>
+```
+
+### ❌ Delete an HPA
+
+Remove a Horizontal Pod Autoscaler:
+
+```bash
+kubectl delete hpa -n <namespace> <hpa-name>
+```
+
+### 🛠️ Edit an HPA
+
+Manually edit an existing HPA configuration:
+
+```bash
+kubectl edit hpa -n <namespace> <hpa-name>
+```
+
+---
+
+## 🧾 Example HPA Manifest
+
+You can define an HPA using a YAML file for more control:
+
+```yaml
+apiVersion: autoscaling/v2
+kind: HorizontalPodAutoscaler
+metadata:
+  name: hpa-test
+  namespace: dev
+spec:
+  minReplicas: 1
+  maxReplicas: 10
+  metrics:
+  - type: Resource
+    resource:
+      name: cpu
+      target:
+        type: Utilization
+        averageUtilization: 50
+```
+
+> ℹ️ **Note:** The above manifest uses API version `autoscaling/v2` for enhanced metric support.
+
+---
+
diff --git a/Containerization & Orchestration/Kubernetes/components/6-DaemonSet.md b/Containerization & Orchestration/Kubernetes/components/6-DaemonSet.md
new file mode 100644
index 0000000..3664ae8
--- /dev/null
+++ b/Containerization & Orchestration/Kubernetes/components/6-DaemonSet.md	
@@ -0,0 +1,40 @@
+# 🧩 DaemonSet in Kubernetes
+
+A **DaemonSet** ensures that a copy of a specific pod runs on **every (or some) node** in the cluster. It’s typically used for background system-level services like log collection, monitoring, or networking tools.
+
+---
+
+## 📌 Key Characteristics
+
+- Automatically deploys one pod per worker node.
+- Ensures the pod stays on each node as long as the DaemonSet exists.
+- Automatically adds pods to new nodes when they join the cluster.
+
+---
+
+## 📄 Example DaemonSet YAML
+
+Below is a simple DaemonSet example that deploys `nginx` to every node in the `web` namespace:
+
+```yaml
+apiVersion: apps/v1
+kind: DaemonSet
+metadata:
+  name: nginx
+  namespace: web
+  labels:
+    app: web-servers
+spec:
+  selector:
+    matchLabels:
+      app: web-servers
+  template:
+    metadata:
+      labels:
+        app: web-servers
+    spec:
+      containers:
+        - name: nginx
+          image: nginx:1.27
+````
+
diff --git a/Containerization & Orchestration/Kubernetes/node-manage.md b/Containerization & Orchestration/Kubernetes/node-manage.md
index 2472b09..f877634 100644
--- a/Containerization & Orchestration/Kubernetes/node-manage.md	
+++ b/Containerization & Orchestration/Kubernetes/node-manage.md	
@@ -1,44 +1,63 @@
+# 🌐 Node Management with Kubernetes
 
-## Node Management
+Efficient management of Kubernetes nodes ensures cluster stability and workload flexibility. Below are key commands for listing and maintaining nodes.
 
-### Listing Nodes
+---
 
-- **Show All Nodes**
+## 📋 Listing Nodes
+
+### 🔹 Show All Nodes
+```bash
+kubectl get nodes
+````
+
+### 🔹 Show Nodes with Labels
+
+```bash
+kubectl get nodes --show-labels
+```
+
+---
+
+## 🔧 Node Maintenance (Cordon / Drain)
+
+### 🚫 Cordon a Node
+
+Prevent new pods from being scheduled on the node.
+
+```bash
+kubectl cordon <node-name>
+```
+
+### ✅ Uncordon a Node
+
+Mark the node as schedulable again.
+
+```bash
+kubectl uncordon <node-name>
+```
+
+### 🧹 Drain a Node
+
+Evict all pods from the node (excluding those managed by DaemonSets).
+
+* Forcefully drain the node:
 
   ```bash
-  kubectl get nodes
+  kubectl drain <node-name> --ignore-daemonsets --force
   ```
 
-
-  ```bash
-    kubectl get nodes --show-lables
-  ```
-
-### Node Maintenance (Cordon/Drain)
-
-- **Cordon a Node**  
-  Prevent new pods from being scheduled on the node.
-
-  ```bash
-  kubectl cordon <node-name>
-  ```
-
-- **Uncordon a Node**  
-  Mark the node as schedulable again.
-
-  ```bash
-  kubectl uncordon <node-name>
-  ```
-
-- **Drain a Node**  
-  Evict all pods from the node (excluding those managed by DaemonSets).
+* Drain and delete local data:
 
   ```bash
   kubectl drain <node-name> --ignore-daemonsets --delete-local-data
   ```
 
-  > **Warning:** Draining a node will evict running pods. Ensure that you plan this action to avoid service disruption.
+#### 🔄 Undo Drain (Uncordon)
 
+```bash
+kubectl uncordon <node-name>
+```
 
----
+> ⚠️ **Warning:** Draining a node will evict running pods. Ensure that this is planned to avoid service disruption.