Skip to content
andrew.dunn.dev

#podman

4 entries

writing · July 2026

Service-to-Service Routing in Rootless Podman

Part one isolated the network planes. The sequel: if every service is in its own plane, how do they talk? The answer is FQDN-everywhere through one always-available local router. Getting there meant a hunt through link-local host access, an SSRF guard that rejected it, pasta's --map-guest-addr, and a careful reading of what podman upstream has actually decided. Plus an epilogue: what happened when the pattern met the whole fleet, and the upstream patch that lets the workaround retire.

Built at GitLab

projects · July 2026

bulkhead

Least-privilege self-managed GitLab CI runners on a fixed set of AlmaLinux hosts: rootless Podman for ordinary jobs, ephemeral libvirt VMs for jobs that need root, and the cgroups v1 versus v2 trap that decides which release to build on.

writing · June 2026

Network Plane Isolation in Rootless Podman

Two podman networks alone don't segment traffic in rootless mode, and isolate=true silently fails when netavark uses its iptables backend (the default on Fedora 43 and earlier) thanks to an iptables-nft bug. The root cause, the fix, and how Fedora 44 made it disappear.

writing · March 2026

Rootless Podman Pods Leak Subordinate UIDs

Rootless Podman pods leak subordinate UIDs onto the host filesystem. The pod abstraction was the constraint, and named networks fix it completely.