242-debug-containers.sh

# Source: https://gist.github.com/vfarcic/9d9de2cf93b6514ab8cf8fed56542352

##################################################################
# How to Debug Kubernetes Applications With Ephemeral Containers #
# https://youtu.be/qKb6loAEPV0                                   #
##################################################################

# Additional Info:
# - Containers Are Not VMs! Which Base Container (Docker) Images Should We Use?: https://youtu.be/82ZCJw9poxM
# - Is Timoni With CUE a Helm Replacement?: https://youtu.be/bbE1BFCs548

#########
# Setup #
#########

# Create a Kubernetes cluster (any should do starting from
#   v1.25).

# Please watch https://youtu.be/bbE1BFCs548 if you are not
#   familiar with Timoni.
timoni --namespace demo apply silly-demo \
    oci://c8n.io/vfarcic/silly-demo-package --version 1.4.37

export POD=$(kubectl --namespace demo get pods \
    --selector app.kubernetes.io/name=silly-demo \
    --output jsonpath='{.items[0].metadata.name}')

########
# Demo #
########

kubectl --namespace demo exec -it $POD -- sh


kubectl --namespace demo debug $POD --image alpine \
    --stdin --tty --target silly-demo

ps aux

exit

kubectl --namespace demo get pod $POD --output yaml

kubectl --namespace demo debug $POD --image alpine \
    --stdin --tty --share-processes --copy-to silly-demo-debug

ps aux

exit

kubectl --namespace demo delete pod silly-demo-debug

###########
# Destroy #
###########

# Destroy or reset the cluster.