https://github.com/kvaps/kubectl-node-shell

Exec into node via kubectl
https://github.com/kvaps/kubectl-node-shell

kubectl kubectl-enter kubectl-node-shell kubectl-plugin kubectl-plugins kubernetes nsenter

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Exec into node via kubectl

• Host: GitHub
• URL: https://github.com/kvaps/kubectl-node-shell
• Owner: kvaps
• License: apache-2.0
• Created: 2019-03-14T20:03:40.000Z (over 5 years ago)
• Default Branch: master
• Last Pushed: 2024-04-24T19:25:51.000Z (7 months ago)
• Last Synced: 2024-05-21T12:42:04.805Z (6 months ago)
• Topics: kubectl, kubectl-enter, kubectl-node-shell, kubectl-plugin, kubectl-plugins, kubernetes, nsenter
• Language: Shell
• Homepage:
• Size: 43.9 KB
• Stars: 1,336
• Watchers: 13
• Forks: 167
• Open Issues: 16
• Metadata Files:
  • Readme: README.md
  • License: LICENSE

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• awesome-starred - kvaps/kubectl-node-shell - Exec into node via kubectl (kubernetes)

README

        
# kubectl node-shell

*(formerly known as **kubectl-enter**)*

Start a root shell in the node's host OS running. Uses an alpine pod with nsenter for Linux nodes and a [HostProcess pod](https://kubernetes.io/docs/tasks/configure-pod-container/create-hostprocess-pod/) with PowerShell for Windows nodes.

![demo](https://gist.githubusercontent.com/kvaps/2e3d77975a844654ec297893e21a0829/raw/c778a8405ff8c686e4e807a97e9721b423e7208f/kubectl-node-shell.gif)

## Installation

using [krew](https://krew.sigs.k8s.io/):

Plugin can be installed from the official krew repository:


kubectl krew install node-shell



Or from our own krew repository:


kubectl krew index add kvaps https://github.com/kvaps/krew-index

kubectl krew install kvaps/node-shell



or using curl:

```bash

curl -LO https://github.com/kvaps/kubectl-node-shell/raw/master/kubectl-node_shell

chmod +x ./kubectl-node_shell

sudo mv ./kubectl-node_shell /usr/local/bin/kubectl-node_shell

```

## Usage

```bash

# Get standard bash shell

kubectl node-shell 

# Use X-mode (mount /host, and do not enter host namespace)

kubectl node-shell -x 

# Execute custom command

kubectl node-shell  -- echo 123

# Use stdin

cat /etc/passwd | kubectl node-shell  -- sh -c 'cat > /tmp/passwd'

# Run oneliner script

kubectl node-shell  -- sh -c 'cat /tmp/passwd; rm -f /tmp/passwd'

```

## X-mode

X-mode can be useful for debugging minimal systems that do not have a built-in shell (eg. Talos).  

Here's an example of how you can debug the network for a rootless kube-apiserver container without a filesystem:

```bash

kubectl node-shell -x 

# Download crictl

wget https://github.com/kubernetes-sigs/cri-tools/releases/download/v1.28.0/crictl-v1.28.0-linux-amd64.tar.gz -O- | \

  tar -xzf- -C /usr/local/bin/

# Setup CRI endpoint

export CONTAINER_RUNTIME_ENDPOINT=unix:///host/run/containerd/containerd.sock

# Find your container

crictl ps | grep kube-apiserver

#3ff4626a9f10e       e7972205b6614       6 hours ago         Running             kube-apiserver         0                   215107b47bd7e       kube-apiserver-talos-rzq-nkg

# Find pid of the container

crictl inspect 3ff4626a9f10e | grep pid

#    "pid": 2152,

#            "pid": 1

#            "type": "pid"

#                "getpid",

#                "getppid",

#                "pidfd_open",

#                "pidfd_send_signal",

#                "waitpid",

# Go to network namespace of the pid, but keep mount namespace of the debug container

nsenter -t 2152 -n

```

*You need to be able to start privileged containers for that.*