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Gentoo Linux & Portage Package Manager

  • Create lightweight, hardened containers with Kubler

    cross-posted from: https://lemmy.srcfiles.zip/post/32334

    > What is Kubler? > --------------- > > Kubler is a generic, extendable build orchestrator, written in Bash. It can be used to take advantage of Portage’s features to build lightweight Docker or Podman images without needing to mess with crossdev, or as a tool to assist with ebuild development. > > Why should you use it? > ---------------------- > > * You like lightweight, easy-to-create, containers > * You want to reduce the attack surface by including only what’s required > * You want to take advantage of USE flags to manage package features > * You want the awesome package library offered by the Gentoo ebuild repository (and other ebuild repos) > * You want up-to-date containers > * You want a containerised environment for building and testing ebuilds > > A real-world example > -------------------- > > I recently needed to integrate a containerised application with a vendor-managed openldap instance that uses mTLS authentication. Unfortunately the containerised application does not work with mTLS and the vendor managed openldap instance can’t be easily configured to use anything else. > > I came up with the solution of using openldap’s lloadd LDAP load balancer daemon to proxy connections from an encrypted internal network to the LDAP server but was left with the issue that I didn’t have a working openldap container that contained lloadd - of the existing containers that I tried the only one that actually had an lloadd bin didn’t actually include required dependencies! > > Glossing over a recent ebuild update to openldap to enable the building of lloadd, enter Kubler - It’s turned out to be an incredibly flexible and hands-off tool compared to trying to accomplish the same thing with (e.g.) Dockerfiles. > > ### Kubler in action > > This (lightly sanitised) real-world example creates create a new namespace called ‘larry’ which may contain multiple images. > > Use the new command to take care of the boilerplate; choose ‘multi’ when asked for the namespace type:\> > $ kubler new namespace larry > »»» > »»» to accept default value > »»» > »»» Working dir type? Choices: > »»» single - You can't add further namespaces to the created working dir, it only holds images > »»» multi - Creates a working dir that can hold multiple namespaces > »[?]» Type (single): multi > »»» > »»» Top level directory name for new namespace 'larry'? The directory is created at /data/development/gentoo-containers/ > »[?]» Namespaces Dir (kubler-images): > »»» > »»»»» Initial image tag, a.k.a. version? > »[?]» Image Tag (20230706): > »»» > »[!]» New namespace location: /data/development/gentoo-containers/kubler-images/larry > »»» > »»»»» Who maintains the new namespace? > »[?]» Name (Your Name): Larry the Cow > »[?]» EMail ([email protected]): [email protected] > »»» > »»»»» Default build engine? > »[?]» Engine (docker): > »»» > »[✔]» Successfully created "larry" namespace at /data/development/gentoo-containers/kubler-images > »»» > »[!]» Configuration file: /data/development/gentoo-containers/kubler-images/larry/kubler.conf > »»» > »[!]» To manage the new namespace with GIT you may want to run: > »»» > »»» $ git init /data/development/gentoo-containers/kubler-images/larry > »»» > »[!]» To create images in the new namespace run: > »»» > »»» $ cd /data/development/gentoo-containers/kubler-images/larry > $ kubler new image larry/ > > > Although not strictly required, installing Kubler’s example images is a good idea. > > $ cd larry/ > $ kubler update > > > It is worthwhile to begin tracking this new namespace with Git so that images can be tracked as they are created and updated. Kubler has already placed a prepopulated a.gitignorefile for convenience. > > pushd /data/development/gentoo-containers/kubler-images/larry > git init . > git add . > git commit -m "Initial commit" > popd > > > Create the new ‘openldap’ within the existing ‘larry’ namespace, based on the ‘kubler/busybox’ image. > > kubler new image larry/openldap > »»» > »»» to accept default value > »»» > »»» Extend an existing Kubler managed image? Fully qualified image id (i.e. kubler/busybox) or scratch > »[?]» Parent Image (scratch): kubler/busybox > »»» > »»» Add test template(s)? Possible choices: > »»» hc - Add a stub for Docker's HEALTH-CHECK, recommended for images that run daemons > »»» bt - Add a stub for a custom build-test.sh script, a good choice if HEALTH-CHECK is not suitable > »»» yes - Add stubs for both test types > »»» no - Fck it, we'll do it live! > »[?]» Tests (hc): yes > »»» > »[✔]» Successfully created new image at /data/development/gentoo-containers/kubler-images/larry/images/openldap > »»» > > > > **Note**: This step is ‘‘not’’ required; it is possible to directly edit thebuild.shfile if you are familiar with Portage. > > Kubler brings a unique feature to the table when constructing an container image: the--interactivebuild argument. As the name implies, this launches the build container in an interactive manner, enabling users to investigate the current / inherited configuration. > > $ kubler build larry/openldap -i > > > This will build any missing parent images/builders; the first run may take quite a bit of time - once the local binary package cache and build containers are seeded future runs will be much faster. Once the prerequisite images are ready the build container will present a shell. > > For first-time users it may be convenient to search for the openldap package to ensure that the correct atom is selected and investigate any USE flags that are of interest: > > # eix openldap > * net-nds/openldap > Available versions: 2.4.59-r2^t 2.5.14(0/2.5)^t 2.6.3-r7(0/2.6)^t ~2.6.4-r1(0/2.6)^t ~2.6.4-r2(0/2.6)^t {argon2 autoca +berkdb +cleartext crypt cxx debug experimental gnutls iodbc ipv6 kerberos kinit minimal odbc overlays pbkdf2 perl samba sasl selinux sha2 smbkrb5passwd ssl static-libs +syslog systemd tcpd test ABI_MIPS="n32 n64 o32" ABI_S390="32 64" ABI_X86="32 64 x32"} > Homepage: https://www.openldap.org/ > Description: LDAP suite of application and development tools > > > Edit the image’s build script: > > nano /config/build.sh > > > > **Note**: The/configdirectory in the build container is the host mounted image directory atlarry/images/openldap/. Feel free to use a local IDE/editor to edit build.shinstead. > > Add thenet-nds/openldapandnet-misc/curlpackages to the_packagesvariable inbuild.sh, update cURL USE flags, enable the ~arch` (~amd64 - the Gentoo ‘testing’ keyword) for packages we care about: > > _packages="net-nds/openldap net-misc/curl" > ... > configure_rootfs_build() > { > # Update a Gentoo package use flag. > update_use 'net-misc/curl' '+ldap' > # ..or a Gentoo package keyword > update_keywords 'net-misc/curl' '+~amd64' > update_keywords 'net-nds/openldap' '+~amd64' > ... > } > > > > Note: If using the busybox image as a parent, unset the `su` USE flag from `sys-apps/util-linux` in the `build.sh`. > > Perform a test run of the first build phase: > > $ kubler-build-root > > > Once this completes successfully exit the interactive builder using `exit`. > > #### Building the image > > Assuming that `build.sh` has been configured as described above, it should be safe to attempt to build the image. > > $ kubler build larry/openldap -nF > »[✘]»[larry/openldap]» fatal: build-test.sh for image larry/openldap:20230704 failed with exit signal: 1 > > > > Note: The arguments are short hand for `--no-deps` and `--force-full-image-build`, omitting `-n` would also rebuild all parent images, which is waste of time in this case. > > The build will fail, as expected, due to the `build-test.sh` script not being implemented. This is a good time to implement the `build-test.sh` script, which will be used to verify that the image is functional. > > > Note: `pipefail` will cause build-test.sh to fail on busybox-based images > > #!/usr/bin/env sh > > set -eo > > # Do some tests and exit with either 0 for healthy or 1 for unhealthy > # Check that the openldap bin launches and provides some expected output > /usr/lib/openldap/lloadd -VV 2>&1 | grep "OpenLDAP" || exit 1 > > exit 0 > > > Unfortunately this image is not suitable for a build-time docker health check via the `docker-healthcheck.sh` mechanism, so must be disabled in `larry/images/openldap/build.conf`: > > POST_BUILD_HC=false > > > A health check suitable for your environment should be provided using standard docker syntax in the image’s `Dockerfile.template` instead. Ensure that the provided `docker-healthcheck.sh` script iS updated (or commented out of the dockerfile) as the default will fail. > > Modify the image’s `Dockerfile.template` to add any finishing touches, such as the `ENTRYPOINT` or `CMD` directives. In this example the container will act as an LDAP proxy via `lloadd`; additional configuration will be provided at runtime by mounting the configuration into the container. > > FROM ${IMAGE_PARENT} > LABEL maintainer="${MAINTAINER}" > > ADD rootfs.tar / > > COPY docker-healthcheck.sh /usr/bin/docker-healthcheck > HEALTHCHECK --interval=60s --timeout=5s --start-period=5s --retries=3 CMD ["docker-healthcheck"] > > CMD ["/usr/lib/openldap/lloadd"] > > > Re-run the build: > > $ kubler build larry/openldap -nF > »[✔]»[larry/openldap]» done. > > > At this point the image should exist in the local Docker/Podman registry and be ready for use: > > docker images > REPOSITORY TAG IMAGE ID CREATED SIZE > larry/openldap 20230704 09347c55282b 2 minutes ago 56.4MB > larry/openldap latest 09347c55282b 2 minutes ago 56.4MB > > > Hopefully this has been useful and you are now ready to build your own images! I’ve been incredibly impressed with how easy it is to use the tool (and it it’ll run from any distro with a recent version of Docker/Podman), and the quality of the resulting images. I’m a recent convert, but have updated the Gentoo Wiki with the above information (and some extra info on using it for ebuild development) and will be using Kubler in future wherever I need to create images. > > Happy containering!

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  • How to set up Podman with NVIDIA GPU acceleration and macvlan networking on Gentoo

    gist.github.com Gentoo with GPU-enabled Podman and MACVLAN

    Gentoo with GPU-enabled Podman and MACVLAN. GitHub Gist: instantly share code, notes, and snippets.

    Gentoo with GPU-enabled Podman and MACVLAN

    cross-posted from: https://lemm.ee/post/2871450

    > Getting GPU acceleration working is a common task for those of us running Plex or Jellyfin. There is not much documentation for getting the NVIDIA container stack to work with Podman, even less on Gentoo, plus there have been a lot of changes to NVIDIA's container toolkit lately. > > I have been fighting with Podman for a while now and just recently got it working 1:1 with my Docker setup. Gentoo may not be the most popular or easy to use distro but I documented it in case some poor soul runs across it searching the web. > > Feel free to poke holes in it or leave feedback.

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  • Do you enable telemetry?

    Speceficially the telemetry use flag. On one hand, fuck telemetry, but on the other hand, I trust FOSS developers to do the right thing vs the likes of Microsoft and Google.

    https://packages.gentoo.org/useflags/telemetry

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  • How long have you been using Gentoo? Linux in general?

    And why do you prefer it over other distros?

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  • Welcome to a new unofficial Gentoo Linux community

    There was already a Gentoo community on Lemmy, however it hasn't had any activity in 2 years and since Lemmy's popularity has exploded in recent days, I figured it might be time for a new one with active moderation.

    Anyone reading this likely already knows what Gentoo is, but on the off-chance that someone completely unfamiliar with Gentoo clicks on this thread, here's a quick primer. Gentoo Linux is essentially a meta-distribution. You're given a package manager (Portage) that builds your packages from source, and some useful command line utilities. Other than that, you get your choice of everything - systemd or OpenRC? X11 or Wayland? Gnome, KDE or some other desktop manager? Or none at all? All up to you. Now of course, Arch provides you the same freedom of choice, but Gentoo's party trick is the local compilation - you can have the compiler optimize everything for your particular CPU's instruction set, or just leave out features you don't need in some programs.

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