GitOps (Argo CD / Flux)
As a Senior engineer, explain GitOps (Argo CD / Flux). What problem does it solve and how would you describe it in an interview?
Answers use simple, clear English.
Audio N/AQuick interview answer
At Senior depth: start with the problem, then mechanism, then a short example. Desired cluster state lives in Git; controller reconciles continuously.
Detailed answer
At Senior depth: start with the problem, then mechanism, then a short example. Desired cluster state lives in Git; controller reconciles continuously. CI builds images; CD is pull-based sync from Git. Auditable deploys. Core: Desired cluster state lives in Git; controller reconciles continuously. CI builds images; CD is pull-based sync from Git. Auditable deploys. Real-time example: Update image tag in GitOps repo → Argo CD syncs Deployment. Pros: Drift detection; easy rollback via Git revert. Cons: Secrets in Git need Sealed Secrets/ESO. Common mistakes: kubectl apply snowflakes bypassing Git. Best practices: PR for prod changes; app-of-apps; progressive sync waves. Audience level: Senior.
Full explanation
Desired cluster state lives in Git; controller reconciles continuously. CI builds images; CD is pull-based sync from Git. Auditable deploys.
Real example & use case
Update image tag in GitOps repo → Argo CD syncs Deployment.
Pros & cons
Pros: Drift detection; easy rollback via Git revert. Cons: Secrets in Git need Sealed Secrets/ESO.
Common mistakes
kubectl apply snowflakes bypassing Git.
Best practices
PR for prod changes; app-of-apps; progressive sync waves.
Follow-up questions
- How would you test GitOps (Argo CD / Flux)?
- What metrics prove GitOps (Argo CD / Flux) is healthy in prod?
- How does GitOps (Argo CD / Flux) change at 10× traffic?