Podman

Installing Podman (under Debian 10)🔗

Skip this section unless you're running Debian 10.

Note: We use "buster-backports" on Debian 10 to get a newer version of libseccomp2.

U1=https://download.opensuse.org/repositories/devel
U2=/kubic:/libcontainers:/stable/Debian_10
U3=devel:kubic:libcontainers:stable.list

cat << END >> /etc/apt/sources.list
deb http://deb.debian.org/debian buster-backports main
END

cat << END >> /etc/apt/sources.list.d/$U3
deb $U1:$U2/ /
END

curl -L $U1:$U2/Release.key | sudo apt-key add -
sudo apt-get update
sudo apt-get -y -t buster-backports install libseccomp2
sudo apt-get -y install podman

Step: Install "podman" (under Ubuntu 18.04).🔗

Skip this section unless you're running Ubuntu 18.04.

MOO=https://download.opensuse.org/repositories/devel:\
/kubic:/libcontainers:/stable/xUbuntu_${VERSION_ID}
echo $MOO

echo "deb $MOO/ /" | \
sudo tee /etc/apt/sources.list.d/\
devel:kubic:libcontainers:stable.list

curl -L $MOO/Release.key | sudo apt-key add -

sudo apt-get update
sudo apt-get -y upgrade
sudo apt-get -y install podman

Instructions online say to do this next, but it doesn't seem to work. We think it's because this part is intended for cases where non-root users are going to use "podman".

systemctl --user restart dbus

Suggestion: At this point, reboot the system instead.

Some notes on “Podman”🔗

You can use podman to pull and run a copy of Ubuntu LTS as follows:

podman image pull ubuntu
podman run --interactive --tty --name sally ubuntu

Ctrl + D to exit.

The preceding block will leave you with a stored image named ubuntu and a stored container named sally. To run sally again :

podman restart sally
podman attach sally

Ctrl + D to exit.

To list `podman` containers :🔗

podman container list --all

podman lacks a simple way to rename containers. This approach is cumbersome but should work.

podman stop    sally            # Stop   old  container
                                # Use container to create image
podman commit  sally jessie-image
podman rm      sally            # Delete old container
                                # Create new container
podman run --interactive --tty --name jessie jessie-image
podman image rm jessie-image    # Optional: Delete new image
# Control-D to exit

To run container again

podman restart jessie
podman attach jessie

Control-D to exit

Exporting a `podman` container to a tarball🔗

podman stop    jessie
podman export  jessie | gzip -c -9 > jessie-image.tar.gz

You can use a tarball of this type to create a new image:

podman import  jessie-image.tar.gz new-jessie-image \
     -c CMD=/bin/bash \
     -c WORKDIR=/tmp \
     -c ENV=PATH=/usr/local/sbin:/usr/local/bin:\
/usr/sbin:/usr/bin:/sbin:/bin

Note: The tarball doesn't preserve meta-information such as what to do with the image when you run it.However, settings related to that can be specified during the image creation step as illustrated above.

So, an alternate and clumsier way to rename a container is as follows:

podman stop    jessie           # Stop   "jessie" container
                                # Create "jessie" tarball
podman export  jessie | gzip -c -9 > jessie-image.tar.gz
                                # Use the tarball to create an image
podman import  jessie-image.tar.gz laura-image \
     -c CMD=/bin/bash \
     -c WORKDIR=/tmp \
     -c ENV=PATH=/usr/local/sbin:/usr/local/bin:\
/usr/sbin:/usr/bin:/sbin:/bin
                                # Delete "jessie" tarball
rm             jessie-image.tar.gz
podman rm      jessie           # Delete "jessie" container
                                # Create "laura"  container
podman run --interactive --tty --name laura laura-image