linkerd / linkerd/linkerd-examples

Local l5d discovery issue in k8s-daemonset example

Open
#45 2 comments 0 reactions 0 assignees View on GitHub

Nobody has claimed this yet.

Dominant language
Go
Stars
444
Forks
216
PR merge metrics
No merged PRs in 30d

Description

When I tried to deploy `k8s-daemonset/k8s/hello-world-1_4.yml` in my **minikube** I ran into an issue where the value given to `spec.nodeName` (`minikube`) wasn't resolvable by kube-dns, causing an exception in `hello.py`. I'm not sure why this wasn't a problem in other k8s deployments. In minikube and k8s 1.4, `hostIP.sh` or similar approach looking up `status.hostIP` may still be necessary.

There is a [proposal](https://github.com/kubernetes/kubernetes/issues/28610) in kubernetes to improve node-local service discovery when using DaemonSets that could solve this issue.

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Start by deploying k8s-daemonset/k8s/hello-world-1_4.yml in minikube and inspect hello.py where kube-dns resolution fails for spec.nodeName. Review hostIP.sh or a similar lookup of status.hostIP, alongside the linked Kubernetes proposal. Done means the example performs node-local service discovery without the exception in this environment.

Written by the indexing model from the issue text.

Assessment

Tech stack
kubernetes, python, shell
Domain
infrastructure, networking
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
30/100

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.