kubectl-execuser

Overview

Exec as a specified user into a Kubernetes container. It has been tested on a kubernetes cluster versions v1.14.X, v1.15.X and 1.16.X.

It works by creating a pod on the same node as the container and mounting the docker socket into this container. The container runs the docker application which has access to the hosts containers and is able to use the exec command with the user flag.

Install

Just clone the plugin script within a folder in your PATH:

wget https://raw.githubusercontent.com/drodbar/kubectl-execuser/master/kubectl-execuser -O /usr/local/bin/kubectl-execuser
chmod +x /usr/local/bin/kubectl-execuser

To check correct installation run:

kubectl plugin list

if the binary path appears in the output, you are ready to go!

Usage

kubectl execuser [options] <podname>

  Options:
    -u|--username  <user>        : user in the pod
    -n|--namespace <namespace>   : namespace containig the pod
    -c|--container <container>   : container within the pod
    -i|--index <index>           : index of the container within the pod
    -s|--shell <shell>           : shell to exec into in the pod
    -d|--debug                   : debug mode shows the variables in the plugin
    -v|--verbose                 : verbose mode
    -h|--help                    : show this help menu

The pod name is the only mandatory argument, and it can be placed anywhere.

Flags

Name	shortopt	longopt	Default	Usage
username	-u	--username	root	Username or UID
namespace	-n	--namespace	default	Namespace: defaults to current or 'default'
container	-c	--container		Container name
index	-i	--index	0	Container index
shell	-s	--shell	sh	Shell to run
debug	-d	--debug		Debug mode
verbose	-v	--verbose		Verbose mode
help	-h	--help		Show help

Examples

Exec into first container in example pod with sh as user root.

kubectl execuser example

Exec into first container in example pod with a bash shell as user root.

kubectl execuser example -s bash

Exec into first container in example pod with bash as user admin.

kubectl execuser -u admin example -s bash

Exec into container 1 within pod example pod with a bash shell and user admin, allowing debug and verbose mode.

kubectl execuser -c 1 -u admin example -s bash -dv

Exec into container container within pod example allowing debug mode.

# defaults to root user and sh shell
kubectl execuser -c container example -d