1.2. Building the bootc image

Procedure

1. Create a Containerfile that includes the following instructions:

   Example Containerfile for RHEL image mode

   FROM registry.redhat.io/rhel9/rhel-bootc:9.4
   
   ARG USHIFT_VER=4.17
   RUN dnf config-manager \
           --set-enabled rhocp-${USHIFT_VER}-for-rhel-9-$(uname -m)-rpms \
           --set-enabled fast-datapath-for-rhel-9-$(uname -m)-rpms
   RUN dnf install -y firewalld microshift && \
       systemctl enable microshift && \
       dnf clean all
   
   # Create a default 'redhat' user with the specified password.
   # Add it to the 'wheel' group to allow for running sudo commands.
   ARG USER_PASSWD
   RUN if [ -z "${USER_PASSWD}" ] ; then \
           echo USER_PASSWD is a mandatory build argument && exit 1 ; \
       fi
   RUN useradd -m -d /var/home/redhat -G wheel redhat && \
       echo "redhat:${USER_PASSWD}" | chpasswd
   
   # Mandatory firewall configuration
   RUN firewall-offline-cmd --zone=public --add-port=22/tcp && \
       firewall-offline-cmd --zone=trusted --add-source=10.42.0.0/16 && \
       firewall-offline-cmd --zone=trusted --add-source=169.254.169.1
   
   # Create a systemd unit to recursively make the root filesystem subtree
   # shared as required by OVN images
   RUN cat > /etc/systemd/system/microshift-make-rshared.service <<'EOF'
   [Unit]
   Description=Make root filesystem shared
   Before=microshift.service
   ConditionVirtualization=container
   [Service]
   Type=oneshot
   ExecStart=/usr/bin/mount --make-rshared /
   [Install]
   WantedBy=multi-user.target
   EOF
   RUN systemctl enable microshift-make-rshared.service

   重要

   Podman uses the host subscription information and repositories inside the container when building the container image. If the rhocp and fast-datapath repositories are not available on the host, the build fails.

2. Create a local bootc image by running the following image build command:

   PULL_SECRET=~/.pull-secret.json
   USER_PASSWD=<your_redhat_user_password> 

   1

   
   IMAGE_NAME=microshift-4.17-bootc
   
   $ sudo podman build --authfile "${PULL_SECRET}" -t "${IMAGE_NAME}" \
       --build-arg USER_PASSWD="${USER_PASSWD}" \
       -f Containerfile

   1

   Replace <your_redhat_user_password> with your password.

   注記

   How secrets are used during the image build:

   • The podman --authfile argument is required to pull the base rhel-bootc:9.4 image from the registry.redhat.io registry.
   • The build USER_PASSWD argument is used to set a password for the redhat user.

Verification

1. Verify that the local bootc image was created by running the following command:

   $ sudo podman images "${IMAGE_NAME}"

   Example output

   REPOSITORY                       TAG         IMAGE ID      CREATED        SIZE
   localhost/microshift-4.17-bootc  latest      193425283c00  2 minutes ago  2.31 GB