Awesome
kubectl-debug plugin
This plugin demonstrates how to use ephemeral
containers to debug running pods. The kubectl debug
command will add an ephemeral container using an arbitrary container
image to the specified pod which can then be attached and used as a shell.
Note: This is proof-of-concept code and not an officially supported Google
product. The functionality of this plugin should eventually be included in
kubectl
proper.
Running
# assumes you have a working KUBECONFIG
$ GO111MODULE="on" go build cmd/kubectl-debug.go
# place the built binary somewhere in your PATH
$ cp ./kubectl-debug /usr/local/bin
# Create a pod to debug
$ cat example.yaml
apiVersion: v1
kind: Pod
metadata:
name: debugtest
spec:
shareProcessNamespace: true
restartPolicy: Always
containers:
- name: nginx
image: nginx:alpine
stdin: true
tty: true
- name: two
image: gcr.io/google_containers/pause-amd64:3.0
stdin: true
tty: true
$ kubectl create -f example.yaml
pod/debugtest created
# Attach a debian debug image
$ kubectl debug debugtest --image alpine --attach
If you don't see a command prompt, try pressing enter.
/ # ps auxww
PID USER TIME COMMAND
1 root 0:00 /pause
6 root 0:00 nginx: master process nginx -g daemon off;
11 101 0:00 nginx: worker process
12 101 0:00 nginx: worker process
13 101 0:00 nginx: worker process
14 101 0:00 nginx: worker process
15 101 0:00 nginx: worker process
16 101 0:00 nginx: worker process
17 101 0:00 nginx: worker process
18 101 0:00 nginx: worker process
19 root 0:00 /pause
24 root 0:00 /bin/sh
29 root 0:00 ps auxww
/ #
Cleanup
You can "uninstall" this plugin from kubectl by simply removing it from your PATH:
$ rm /usr/local/bin/kubectl-debug