Fedora calls for testing of Rust-rewritten conmon v3 container monitor

The Podman and Fedora Quality teams are asking users to test conmon v3 during a dedicated test week. The new version rewrites the container monitor in Rust to reduce memory safety errors and improve the logging backend interface. Testers can install conmon-v3 via dnf and select it system-wide through a containers.conf drop-in file. The teams want feedback on interactive sessions, Quadlet services, logging behavior, and runtime compatibility across different setups.

What to test and how to switch

• Install with sudo dnf install conmon-v3, then activate via /etc/containers/containers.conf.d/99-conmon-v3.conf with conmon_path = ["/usr/bin/conmon-v3"]
• Verify with podman info that conmon path is /usr/bin/conmon-v3 and version starts with 3
• Running containers keep their existing monitor; only new containers use v3
• Key test areas: interactive shell resize/attach/detach, podman exec output and exit status, file and journald logs with large output and unterminated lines, Quadlet/systemd service lifecycle, rootless vs rootful, crun vs runc
• Watch for hangs, missing output, incorrect exit codes, unexpected CPU usage, or any divergence from conmon v2 behavior

Why it matters

A successful Rust rewrite of conmon could improve memory safety for a core component used by millions of Podman containers, while the shared logging interface may make it easier to add new log backends in the future.