alexei-led / nsenter

Slim nsenter Docker image - enter into Docker container/host namespaces

nsenter

Info

alexeiled/nsenter Docker image is a scratch image that contains only one statically linked nsenter file.

Usage

Read the official nsenter documentation.

Continuously Updated with GitHub Actions

The nsenter is automatically updated when a new version of util-linux is released.

How do I use alexeiled/nsenter?

Enter the container:

# enter all namespaces of selected container
docker run -it --rm --privileged --pid=container:<container_name_or_ID> alexeiled/nsenter --all --target 1 -- su -

Enter the Docker host:

# enter all namespaces of Docker host
docker run -it --rm --privileged --pid=host alexeiled/nsenter --all --target 1 -- su -

Enter Kubernetes node

Use helper script nsenter-node.sh to enter into any Kubernetes node by creating a new pod tolerated to the specified node.

# list Kubernetes nodes
kubectl get nodes

NAME                                            STATUS   ROLES    AGE     VERSION
ip-192-168-151-104.us-west-2.compute.internal   Ready    <none>   6d17h   v1.13.7-eks-c57ff8
ip-192-168-171-140.us-west-2.compute.internal   Ready    <none>   5d10h   v1.13.7-eks-c57ff8

# enter into selected node with default shell as superuser
./nsenter-node.sh ip-192-168-151-104.us-west-2.compute.internal

[root@ip-192-168-171-140 ~]#

nsenter's Issues

Error on container start failed to execute su

This is happening on the existing 2.36 container, and on latest

...
    "containers": [
      {
        "name": "nsenter",
        "image": "ghcr.io/alexei-led/nsenter:latest",
        "command": [
          "/nsenter", "-m", "-u", "-i", "-n", "-p", "-C", "-r", "-w", "--target=1", "--", "su", "-"
        ],
        "imagePullPolicy": "Always",
        "stdin": true,
        "tty": true,
        "securityContext": {
          "privileged": true
        },
        "resources": {
          "requests": {
            "cpu": "10m"
          }
        }
      }
    ]
  }
}
nsenter: failed to execute su: No such file or directory

how to terminate the pod when exit from shell

when exit from the shell, the pod is still runing. Can we terminate the pod when we exit from the shell?

nsenter: cannot open /proc/1/ns/cgroup: No such file or directory

Hi,

I am getting nsenter: cannot open /proc/1/ns/cgroup: No such file or directory when following your steps.

Any idea why?