Using SLE BCI

Package manager

The default package manager in SUSE Linux Enterprise is Zypper. Similar to APT in Debian and APK in Alpine Linux, Zypper offers a command-line interface for all package management tasks. Below is brief overview of commonly used container-related Zypper commands.

Install packages

zypper --non-interactive install $PACKAGE_NAME

Add a repository

zypper --non-interactive addrepo $REPOSITORY_URL; zypper --non-interactive refresh

Update all packages

zypper --non-interactive update

Remove a package

zypper --non-interactive remove --clean-deps $PACKAGE_NAME

the --clean-deps flag ensures that no longer required dependencies are removed as well

Clean up temporary files

zypper clean

For more information on using Zypper, refer to the zypper documentation.

All the described commands use the --non-interactive flag to skip confirmations, since you cannot approve these manually during container builds. Keep in mind that you must use the flag with any command that modifies the system. Also note that --non-interactive is not a "yes to all" flag. Instead, --non-interactive confirms what is considered to be the intention of the user. For example, an installation command with the --non-interactive option fails if it needs to import new repository signing keys, as that is something that the user should verify themselves.

Common patterns

Here are a few examples that can give you an idea how to accomplish certain tasks in SLE BCI compared to Debian.

Remove orphaned packages

Debian: apt-get autoremove -y
SLE BCI: Not required as long as you remove installed packages using the zypper --non-interactive remove --clean-deps $PACKAGE_NAME

Obtain container’s architecture

Debian: dpkgArch="$(dpkg --print-architecture | awk -F- '{ print $NF }')"
SLE BCI: arch="$(uname -p|sed 's/x86_64/amd64/')"

Install packages required for compilation

Debian: apt-get install -y build-essential
SLE BCI: zypper -n in gcc gcc-c++ make

Verify GnuPG signatures

Debian: gpg --batch --verify $SIGNATURE_URL $FILE_TO_VERIFY
SLE BCI: zypper -n in dirmngr; gpg --batch --verify $SIGNATURE_URL $FILE_TO_VERIFY; zypper -n remove --clean-deps dirmngr; zypper -n clean

Package naming conventions

SUSE Linux Enterprise package naming conventions differ from Debian, Ubuntu, and Alpine, and they are closer to those of Red Hat Enterprise Linux. The main difference is that development packages of libraries (that is, packages containing headers and build description files) are named $PACKAGE-devel in SUSE Linux Enterprise, as opposed to $PACKAGE-dev as they are in Debian and Ubuntu. When in doubt, search for the package directly using the following command:

Docker

docker run --rm registry.suse.com/bci/bci-base:$OS_VERSION zypper search $PACKAGE_NAME

Podman

podman run --rm registry.suse.com/bci/bci-base:$OS_VERSION zypper search $PACKAGE_NAME

nerdctl

nerdctl run --rm registry.suse.com/bci/bci-base:$OS_VERSION zypper search $PACKAGE_NAME

(replace OS_VERSION with the appropriate service version number, for example: 15.3 or 15.4).

Adding GPG signing keys

Adding external repositories to a container or container image normally requires importing the GPG key used for signing the packages. This can be done with the rpm --import $KEY_URL command. This adds the key to the RPM database, and all packages from the repository can be installed afterwards.