Engineering

Field reports from production infrastructure: what broke, how it was diagnosed, and what the evidence actually showed.

2026-07-30
Why pods cannot reach Docker Compose services after migrating K3s from Flannel to Cilium
Cilium 1.19.6 GA on Kubernetes 1.36 (K3s) with Docker Engine 29, in a hybrid Compose/Kubernetes estate — a combination we found no published account of at the time of writing. A production field report on a failure mode where the packet is judged one netfilter table earlier than the boundary you own.

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