kubernetes on Alekc's Blog

Useful debugging tools for kubernetes

Sat, 03 Dec 2022 00:00:00 +0000

Sometimes its useful to be able to run some ephemeral containers on kubernetes cluster in order to perform some debugging (i.e. dns resolution, pinging nodes, etc). Sadly, most of the times, it can be tricky to remember all overrides so here is a small list Run an ephemeral shell on a random node 1kubectl run -ti --restart=Never --rm debug --image=alekcander/network-diag -- sh Run a container with specific service account 1kubectl run -ti --restart=Never --rm debug --image=alekcander/network-diag --overrides='{ "spec": { "serviceAccount": "terraform-runner" } }' -- sh Run on a specific node 1kubectl run -ti --restart=Never --rm debug --image=alekcander/network-diag --overrides='{"spec": { "nodeName": "alekc-worker-01"}}' -- sh Run based on specific selector (ie.

How to create terraform iam roles for irsa functionality

Tue, 18 Jan 2022 16:00:00 +0000

IRSA (IAM role for service account) is a very useful tool which permits us to provide AWS permissions to the containers in any pod that uses that service account. This enables us to give a very granular permission setting for specific service accounts and remove most of the headache related to authentication and persisting of secrets.

Below a quick snippet of how to create such mechanism.

Use terraform http data source to wait for cluster coming up

Tue, 18 Jan 2022 00:00:00 +0000

Neat example of how we can use terraform http data source to wait for our kubernetes cluster to come up with a healthy state (shamelessly taken from some github repo)