Build a new Clear Linux OS-based container image¶
This guide describes how to build a new Clear Linux* OS-based container image. The official base Clear Linux* OS container image is published on Docker* Hub and is updated on a regular basis.
Prerequisites¶
You must perform these steps on a Clear Linux OS system because the swupd is used to manage bundles in the container.
You must install the
containers-basic
bundle on the Clear Linux OS system or Docker will not work.You have a basic understanding of Docker.
Build the base container image¶
Log in and get root privileges.
sudo -s
Verify Docker is installed and running.
docker info
If Docker is installed and running, the output is similar to this example:
Containers: 0 Running: 0 Paused: 0 Stopped: 0 Images: 4 Server Version: 17.05.0-ce Storage Driver: overlay Backing Filesystem: extfs Supports d_type: true Logging Driver: json-file Cgroup Driver: cgroupfs Plugins: Volume: local Network: bridge host macvlan null overlay Swarm: inactive Runtimes: runc Default Runtime: runc Init Binary: docker-init containerd version: (expected: 9048e5e50717ea4497b757314bad98ea3763c145) runc version: N/A (expected: 9c2d8d184e5da67c95d601382adf14862e4f2228) init version: N/A (expected: ) Kernel Version: 4.12.7-377.native Operating System: Clear Linux OS for Intel Architecture OSType: linux Architecture: x86_64 CPUs: 4 Total Memory: 15.62GiB Name: clr-os ID: XQHJ:DYEM:3Q4D:DKLM:JOA4:RUSF:GAFR:DLPA:HOJP:W5FF:ULEE:7HZ3 Docker Root Dir: /var/lib/docker Debug Mode (client): false Debug Mode (server): false Registry: https://index.docker.io/v1/ Experimental: false Insecure Registries: 127.0.0.0/8 Live Restore Enabled: false
If Docker is not installed, enter the commands:
swupd bundle-add containers-basic systemctl start docker
Use os-install to download and install the bundles.
swupd os-install --url https://cdn.download.clearlinux.org/update --statedir "$PWD"/swupd-state --no-boot-update -B os-core-update,editors,network-basic base
The swupd example uses the following flags:
os-install tells swupd to download and install.
--url specifies the URL of the bundles repository.
--statedir specifies the state directory where downloaded bundles and any state information are stored.
--no-boot-update tells swupd to skip updating boot files because boot files are not required for a container.
For more information on swupd flags, enter the swupd os-install -h command.
Example output:
swupd-client software verify 3.12.2 Copyright (C) 2012-2017 Intel Corporation Verifying version 17870 Attempting to download version string to memory Downloading packs... Extracting python-basic pack for version 17820 ...14% Extracting perl-basic pack for version 17790 ...28% Extracting openssh-server pack for version 17660 ...42% Extracting editors pack for version 17850 ...57% Extracting network-basic pack for version 17650 ...71% Extracting os-core pack for version 17870 ...85% Extracting os-core-update pack for version 17870 ...100% Adding any missing files ...88% Inspected 33982 files 33974 files were missing 33974 of 33974 missing files were replaced 0 of 33974 missing files were not replaced Calling post-update helper scripts. WARNING: boot files update skipped due to --no-boot-update argument Fix successful
Note
The WARNING message is expected and can be ignored.
Create a tarball and compress it.
tar -C base -cf base.tar . xz -v -T0 base.tar
Create the Dockerfile to build the image.
cat > Dockerfile << EOF FROM scratch MAINTAINER First Last <first.last@example.com> ADD base.tar.xz / CMD ["/bin/bash"] EOF
Build the Clear Linux OS container image.
docker build -t my-custom-clear-linux-container .
Example output:
Sending build context to Docker daemon 806.5MB Step 1/4 : FROM scratch ---> Step 2/4 : MAINTAINER First Last <first.last@example.com> ---> Running in 7238f35abcd0 ---> ec5064287c60 Removing intermediate container 7238f35abcd0 Step 3/4 : ADD base.tar.xz / ---> 2723b7d20716 Removing intermediate container 16e3ed0df8da Step 4/4 : CMD /bin/bash ---> Running in efa893350647 ---> 5414c3a12993 Removing intermediate container efa893350647 Successfully built 5414c3a12993 Successfully tagged my-custom-clear-linux-container:latest
List the newly created Clear Linux OS container image.
docker images
Example output:
REPOSITORY TAG IMAGE ID CREATED SIZE my-custom-clear-linux-container latest 5414c3a12993 About a minute ago 616MB
Launch the built Clear Linux OS container.
docker run -it my-custom-clear-linux-container
Manage bundles in a container¶
You can add and remove bundles from a Clear Linux OS container using the RUN swupd command in the Dockerfile.
Add a bundle¶
This example Dockerfile adds the pxe-server
bundle to an existing Clear Linux OS
Docker image:
cat > Dockerfile << EOF
FROM my-customer-clear-linux-container
MAINTAINER First Last <first.last@example.com>
RUN swupd bundle-add pxe-server
CMD ["/bin/bash/bash"]
EOF
Example output:
docker build -t my-clearlinux-with-pxe-server-bundle .
Sending build context to Docker daemon 806.5MB
Step 1/4 : FROM my-custom-clear-linux-container
---> 5414c3a12993
Step 2/4 : MAINTAINER First Last <first.last@example.com>
---> Running in 19b4411cf4bd
---> 08d400baffde
Removing intermediate container 19b4411cf4bd
Step 3/4 : RUN swupd bundle-add pxe-server
---> Running in 3e634d6e0792
swupd-client bundle adder 3.12.2
Copyright (C) 2012-2017 Intel Corporation
Attempting to download version string to memory
Downloading packs...
Extracting pxe-server pack for version 17820
.
Installing bundle(s) files...
..............................................................................
..............................................................................
..............................................................................
..............................................................................
..............................................................................
..............................................................................
Calling post-update helper scripts.
WARNING: systemctl not operable, unable to run systemd update triggers
Bundle(s) installation done.
---> 8ead5f2c0c33
Removing intermediate container 3e634d6e0792
Step 4/4 : CMD /bin/bash
---> Running in 0ceae320279b
---> dcd9adb40611
Removing intermediate container 0ceae320279b
Successfully built dcd9adb40611
Successfully tagged my-clearlinux-with-pxe-server-bundle:latest
Note
The WARNING message can be ignored because systemd does not run inside a container.
Remove a bundle¶
This example Dockerfile removes the pxe-server
bundle from an existing
Clear Linux OS Docker image:
cat > Dockerfile << EOF
FROM my-clearlinux-with-pxe-server-bundle
MAINTAINER First Last <first.last@example.com>
RUN swupd bundle-remove pxe-server
CMD ["/bin/bash/bash"]
EOF
Example output:
docker build -t my-clearlinux-remove-pxe-server-bundle .
Sending build context to Docker daemon 806.5MB
Step 1/4 : FROM my-clearlinux-with-pxe-server-bundle
---> dcd9adb40611
Step 2/4 : MAINTAINER First Last <first.last@example.com>
---> Running in 71b60f15003e
---> 742192751c1a
Removing intermediate container 71b60f15003e
Step 3/4 : RUN swupd bundle-remove pxe-server
---> Running in ad28a3390ecc
swupd-client bundle remover 3.12.2
Copyright (C) 2012-2017 Intel Corporation
Removing bundle: pxe-server
Deleting bundle files...
Total deleted files: 92
Untracking bundle from system...
Success: Bundle removed
1 bundle(s) were removed successfully
---> d6ee7903e14d
Removing intermediate container ad28a3390ecc
Step 4/4 : CMD /bin/bash
---> Running in 7694989e97de
---> ec23189ef954
Removing intermediate container 7694989e97de
Successfully built ec23189ef954
Successfully tagged my-clearlinux-remove-pxe-server-bundle:latest