conmon is a lightweight C container monitor. It launches the configured OCI runtime, remains after Podman exits, monitors the container, reports its exit status, and manages interaction with its standard streams. section 4.1 section 6.2.4
conmon connects Podman’s control flow with the running container by:
- Passing the OCI specification and rootfs path to crun or runc. section 4.1
- Providing a socket for attach operations and monitoring STDIN, STDOUT, and STDERR. section 6.2.5
- Writing STDOUT and STDERR to logs and reporting the container’s exit code to Podman. section 4.1
- Running cleanup after the container exits, including in rootless workflows. section 6.2.4
Detached container
podman run -d -p 8080:8080 --name myapp registry.access.redhat.com/ubi8/httpd-24 leaves Podman detached while conmon continues monitoring the container; podman attach reconnects through conmon. section 6.2.5
The launch diagram shows Podman starting conmon, which then starts the OCI runtime. section 6.2.4
