Network Utilities Docker Image

This project provides a Docker image based on Alpine with a collection of essential network utilities. These tools are useful for network diagnostics, testing, and troubleshooting.

Project Goals

• Provide a convenient, ready-to-use image for in-cluster network diagnostics.
• Keep the image lightweight while including essential tooling.
• Offer a familiar Bash environment with autocompletion for productive interactive use.
• Ensure compatibility with Kubernetes workflows (e.g., kubectl exec/debug).
• Deliver an image tailored to my own requirements.

Included Utilities

The Docker image includes the following packages:

• bash: GNU Bourne-Again SHell with bash-completion.
• bash-completion: Command-line tab completion and hints for Bash to improve interactive shell usability.
• bind-tools: DNS utilities including dig and nslookup.
• busybox-extras: Additional utilities including telnet.
• curl: Command-line tool for transferring data with URLs, supporting various protocols.
• iproute2: Collection of utilities for network management, including ip.
• iputils: Tools to send ICMP ECHO_REQUEST to network hosts using ping.
• jq: Lightweight and flexible command-line JSON processor for parsing and querying API responses.
• nmap: Network exploration tool and security/port scanner.
• tcpdump: Command-line packet analyzer.
• traceroute: Print the route packets take to a network host.
• vim: Vi IMproved, a programmers text editor.
• wget: Command-line utility for retrieving files from the web.
• yq: YAML processor with jq-like syntax, useful for parsing and modifying Kubernetes manifests and other YAML files.

Usage in Kubernetes

To deploy this image in a Kubernetes cluster, you can use the following deployment manifest. This setup allows you to run the network utilities in a pod.

Deployment Manifest

apiVersion: apps/v1
kind: Deployment
metadata:
  name: netutils
spec:
  replicas: 1
  selector:
    matchLabels:
      app: netutils
  template:
    metadata:
      labels:
        app: netutils
    spec:
      containers:
        - name: netutils
          image: nikitamishagin/netutils:latest
          command: [ "/bin/bash", "-c", "sleep infinity" ]
          # Uncomment below to run as a privileged pod
          # securityContext:
          #   privileged: true
      # Uncomment and modify nodeSelector below for specific node assignment
      # nodeSelector:
      #   kubernetes.io/hostname: specific-node
      # Uncomment the line below to enable host networking
      # hostNetwork: true
      dnsPolicy: ClusterFirst  # Default policy which uses cluster DNS first
      # Available options:
      # - ClusterFirst: Use cluster DNS service first, falling back to upstream DNS servers.
      # - ClusterFirstWithHostNet: Similar to ClusterFirst, but used when host networking is enabled (hostNetwork: true).
      # - Default: Use the default DNS resolver configured on the node.
      # - None: No DNS settings will be provided by the cluster. Use dnsConfig for custom DNS.
      # dnsConfig:
      #   nameservers:
      #     - 8.8.8.8
      #     - 8.8.4.4
      #   searches:
      #     - example.com
      #   options:
      #     - name: ndots
      #       value: "2"

Example Usage

Once deployed, you can exec into the pod and use the network utilities:

kubectl exec -it deployments/netutils -- bash

Then, you can run any of the utilities as needed.

Using with kubectl debug

You can also use this image with kubectl debug to troubleshoot existing pods:

# Attach netutils container to an existing pod
kubectl debug -it pod/your-pod-name --image=nikitamishagin/netutils:latest

# Debug a node with netutils (requires privileged access)
kubectl debug node/your-node-name -it --image=nikitamishagin/netutils:latest

The image is configured with bash as the entrypoint for kubectl debug compatibility.

CI/CD

This project includes a GitHub Actions workflow configured to automatically build and push the Docker image to Docker Hub whenever a new tag is pushed to the repository. The image is tagged with both the specific Git tag and latest.

License

This project is licensed under the Apache License 2.0. See the LICENSE file for details.