nettools

Nettools to debugs. Container image with network tools for troubleshooting Kubernetes clusters

• To check some networking issues in a cluster:

kubectl run -it --image=ghcr.io/duyhenryer/nettools:2.0.1 nettools --restart=Never -n default

• Pod template example:

apiVersion: v1
kind: Pod
metadata:
  name: nettools
  namespace: default
spec:
  containers:
  - name: nettools
    image: ghcr.io/duyhenryer/nettools:2.0.1
    command: ["/bin/sleep", "infinity"]
    imagePullPolicy: IfNotPresent
  restartPolicy: Never

• Deplyment template example:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nettools
  namespace: default
spec:
  replicas: 1
  selector:
    matchLabels:
      app: nettools
  template:
    metadata:
      labels:
        app: nettools
    spec:
      containers:
      - name: nettools
        image: ghcr.io/duyhenryer/nettools:2.0.1
        command: ["/bin/sleep", "infinity"]
        imagePullPolicy: IfNotPresent

You can keep the following yaml file handy and run it in a pod

kubectl apply -f nettools.yaml

and login to the container

kubectl exec -it nettools -n default bash

• If you just want to use the network tools on a docker host:

docker run -it ghcr.io/duyhenryer/nettools:2.0.1 sh

Sample Use-cases

tcpdump is a powerful and common packet analyzer that runs under the command line. It allows the user to display TCP/IP and other packets being transmitted or received over an attached network interface.

tcpdump -i eth0 port 9999 -c 1 -Xvv

More info on tcpdump can be found here.

netstat is a useful tool for checking your network configuration and activity.

netstat -tulpn