Demystifying CRI

on YouTube ↗31m

" summary

Shows how a custom CRI is implemented end-to-end: a Go gRPC/protobuf server that implements the CRI API, uses gRPC/protobuf for messages, invokes runC to spawn a sandbox based on the pause image, calls the CNI to wire the sandbox network namespace, and launches containers by rewriting their namespace to that sandbox. The example runtime is ~300 lines of code, pulls images, creates sandboxes, starts an httpd pod and verifies it via curl localhost; code is available in the linked GitHub repo.

AI-written summary · about

" chapters (11)

1. 0:00Introduction
2. 1:12False advertisement and CRI
3. 3:20CRI prerequisites
4. 6:31CRI versus runtime
5. 9:44gRPC and Protobuf basics
6. 12:36Linux namespaces and isolation
7. 17:58CNI and sandbox creation
8. 19:23Writing CRI demo setup
9. 25:50Implementing CRI service
10. 27:39Live demo verification
11. 28:00Q&A

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