Operations Cheatsheet

We periodically need to perform various tasks that can be quickly described by short shell fragments. This page is meant to be a dumping ground for them. It may be useful on occasion to move such fragments into more relevant pages.

Get Root Access in a User Pod

It can be useful to run commands as root in a user’s pod to quickly install or reconfigure software. This could be done during the development of a PR to change a user image.

In this fragment, local$ conveys operations performed on your own device and node$ shows operations performed on the cloud node.

local$ pod=jupyter-username
local$ ns=datahub-prod

# Obtain and display the user's container ID
local$ cid=$(kubectl -n $ns get pod $pod -o jsonpath="{.status.containerStatuses[].containerID}" | sed 's,.*//,,')
local$ echo $cid

# ssh into the node hosting the user's pod, substituting `NODE_NAME`
local$ kubectl -n $ns get pod $pod -o wide
local$ gcloud compute ssh --zone us-central1-b --project ucb-datahub-2018 NODE_NAME

# Exec into the user's container as root, where `CID_FROM_ABOVE` is the
# value of $cid from above
node$ sudo -i
node# runc --root /run/containerd/runc/k8s.io/ exec -t -u 0 CID_FROM_ABOVE bash