Hello. I have tried Podman in Fedora 31. Not a rootless setup. Software versions: podman-1.6.2-2.fc31.x86_64 containernetworking-plugins-0.8.2-2.1.dev.git485be65.fc31.x86_64 I have created two containers: # podman container run -d --name nginx_1 -p 80:80 nginx # podman container run -d --name nginx_2 -p 81:80 nginx Then I wanted to make sure that they start on boot. According to RHEL 7 documentation, https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux_at... , I am supposed to create systemd units. OK, let's take the documented form of the unit and turn it into a template: [Unit] Description=Container %i [Service] ExecStart=/usr/bin/podman start -a %i ExecStop=/usr/bin/podman stop -t 2 %i [Install] WantedBy=multi-user.target This doesn't work if there is more than one container. The error is: Nov 04 21:35:57 podman[2268]: time="2019-11-04T21:35:57+05:00" level=error msg="Error adding network: failed to allocate for range 0: 10.88.0.19 has been allocated to ace2de4405205a9a7674a2524cd67c1f0e395a9234b0456c55881a1a4add6019, duplicate allocation is not allowed" Nov 04 21:35:57 podman[2268]: time="2019-11-04T21:35:57+05:00" level=error msg="Error while adding pod to CNI network \"podman\": failed to allocate for range 0: 10.88.0.19 has been allocated to ace2de4405205a9a7674a2524cd67c1f0e395a9234b0456c55881a1a4add6019, duplicate allocation is not allowed" Nov 04 21:35:57 podman[2268]: Error: unable to start container ace2de4405205a9a7674a2524cd67c1f0e395a9234b0456c55881a1a4add6019: error configuring network namespace for container ace2de4405205a9a7674a2524cd67c1f0e395a9234b0456c55881a1a4add6019: failed to allocate for range 0: 10.88.0.19 has been allocated to ace2de4405205a9a7674a2524cd67c1f0e395a9234b0456c55881a1a4add6019, duplicate allocation is not allowed (as you can see, the conflict is against the container itself) Apparently different runs of podman need to be serialized against each other. This works: [Unit] Description=Container %i Wants=network-online.target After=network-online.target [Service] Type=oneshot RemainAfterExit=yes ExecStart=flock /run/lock/subsys/container.lck /usr/bin/podman start %i ExecStop=/usr/bin/podman stop -t 2 %i [Install] WantedBy=multi-user.target Questions: a) Why isn't some equivalent of this unit shipped with podman? Or, am I missing some package that ships it? b) Why isn't the necessary locking built into podman itself? Or, is it a bug in containernetworking-plugins? -- Alexander E. Patrakov