Podman (the POD MANager) is an OCI-compliant container engine, developed by Red Hat as a drop-in replacement of Docker. It is used to manage and run, containers, images, and volumes via a command-line interface. Both Docker and Podman are similar software. The only difference is that Podman doesn’t require a daemon to run containers, while Docker needs the Docker Engine daemon. Podman uses the libpod library to manage an entire container ecosystem.
In this tutorial, we will show you how to install and use Podman on Debian 11.
Prerequisites
- A server running Debian 11.
- A root password is configured on the server.
Install Podman
The Podman package is included in the Debian 11 default repository. You can install it by just running the following command:
apt-get install podman -y
Once the Podman is installed, verify the Podman version using the command below:
podman --version
You should see the Podman version in the following output:
podman version 3.0.1
You can get more information of Podman using the following command:
podman info
You will get the following output:
host:
arch: amd64
buildahVersion: 1.19.6
cgroupManager: systemd
cgroupVersion: v2
conmon:
package: 'conmon: /usr/bin/conmon'
path: /usr/bin/conmon
version: 'conmon version 2.0.25, commit: unknown'
cpus: 2
distribution:
distribution: debian
version: "11"
eventLogger: journald
hostname: debian11
idMappings:
gidmap: null
uidmap: null
kernel: 5.10.0-8-amd64
linkmode: dynamic
memFree: 3365183488
memTotal: 4122267648
ociRuntime:
name: crun
package: 'crun: /usr/bin/crun'
path: /usr/bin/crun
version: |-
crun version 0.17
commit: 0e9229ae34caaebcb86f1fde18de3acaf18c6d9a
spec: 1.0.0
+SYSTEMD +SELINUX +APPARMOR +CAP +SECCOMP +EBPF +YAJL
os: linux
remoteSocket:
exists: true
path: /run/podman/podman.sock
security:
apparmorEnabled: true
capabilities: CAP_CHOWN,CAP_DAC_OVERRIDE,CAP_FOWNER,CAP_FSETID,CAP_KILL,CAP_NET_BIND_SERVICE,CAP_SETFCAP,CAP_SETGID,CAP_SETPCAP,CAP_SETUID,CAP_SYS_CHROOT
rootless: false
seccompEnabled: true
selinuxEnabled: false
Add OCI Registry
Podman uses the registry configuration file /etc/containers/registries.conf to pull all container images from the internet. So you will need to edit it and define the registry:
nano /etc/containers/registries.conf
Add the following lines at the end of the file:
[registries.insecure] registries = [ ] # If you need to block pull access from a registry, uncomment the section below # and add the registries fully-qualified name. # Docker only [registries.block] registries = [ ]
Save and close the file when you are finished.
How to Use Podman
In this section, we will show you how to use the Podman command to pull images and run a container.
To pull a Debian image, run the following command:
podman pull debian
You will get the following output:
Resolved "debian" as an alias (/etc/containers/registries.conf.d/shortnames.conf) Trying to pull docker.io/library/debian:latest... Getting image source signatures Copying blob 647acf3d48c2 done Copying config 827e561138 done Writing manifest to image destination Storing signatures 827e5611389abf13dad1057e92f163b771febc0bcdb19fa2d634a7eb0641e0cc
You can see your downloaded image using the following command:
podman images
You will get the following output:
REPOSITORY TAG IMAGE ID CREATED SIZE docker.io/library/debian latest 827e5611389a 11 days ago 129 MB
Next, run a container from the Debian image using the following command:
podman run -dit debian:latest
You will get the following output:
f85c4df5ab787912c984ec820571da7b95b32736ef94ba691d9ab5019c5b5103
You can list all running containers using the following command:
podman ps
You should see the following output:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES f85c4df5ab78 docker.io/library/debian:latest bash 13 seconds ago Up 13 seconds ago competent_cori
To inspect the running container, run the Podman command by specifying container ID:
podman inspect f85c4df5ab78
You will get the following output:
[
{
"Id": "f85c4df5ab787912c984ec820571da7b95b32736ef94ba691d9ab5019c5b5103",
"Created": "2021-11-28T07:00:12.795302341Z",
"Path": "bash",
"Args": [
"bash"
],
"State": {
"OciVersion": "1.0.2-dev",
"Status": "running",
"Running": true,
"Paused": false,
"Restarting": false,
"OOMKilled": false,
"Dead": false,
"Pid": 6881,
"ConmonPid": 6878,
"ExitCode": 0,
"Error": "",
"StartedAt": "2021-11-28T07:00:13.551753552Z",
"FinishedAt": "0001-01-01T00:00:00Z",
"Healthcheck": {
"Status": "",
"FailingStreak": 0,
"Log": null
}
},
To check the container log, run the following command:
podman logs f85c4df5ab78
If you want to connect to the running container, run the following command:
podman exec -it f85c4df5ab78 /bin/bash
You will get into the container shell as shown below:
root@f85c4df5ab78:/#
To exit from the container shell, run the following command:
root@f85c4df5ab78:/# exit
How to Stop and Remove a Container
You can also use Podman to start, stop, and remove a container.
To stop a running container, run the following command:
podman stop f85c4df5ab78
You can now verify the stopped container using the following command:
podman ps -a
You should see the following output:
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES f85c4df5ab78 docker.io/library/debian:latest bash 3 minutes ago Exited (137) 10 seconds ago competent_cori
To remove a stopped container, run the following command:
podman rm f85c4df5ab78
If you want to stop the latest container, run the following command:
podman stop --latest
To start the latest container, run the following command:
podman start --latest
To remove the latest container, run the following command:
podman rm --latest
To remove all running containers, run the following command:
podman rm -f `podman ps -aq`
To remove an image, run the following command:
podman rmi 827e5611389a
You will get the following output:
Untagged: docker.io/library/debian:latest Deleted: 827e5611389abf13dad1057e92f163b771febc0bcdb19fa2d634a7eb0641e0cc
Getting Started with Podman
A detailed guide on how to use Podman to create images, volumes, and containers is available here: Getting Started with Podman: Manage Images, Containers and Volumes
Conclusion
In the above post, we explained how to install and use the Podman on Debian 11. You can now use Podman as a replacement for Docker to run and manage the containers.