Chapter 2. Embedding Red Hat build of MicroShift in a RHEL for Edge image

Procedure

1. Enable the Red Hat build of MicroShift RPM repositories on the build host by running the following command:

   $ sudo subscription-manager repos
       --enable rhocp-4.12-for-rhel-8-$(uname -i)-rpms
       --enable fast-datapath-for-rhel-8-$(uname -i)-rpms

2. Install the reposync and createrepo tools by running the following command:

   $ sudo yum install -y yum-utils createrepo

3. Sync the Red Hat build of MicroShift RPM packages to your build host by running the following command:

   $ sudo reposync --arch=$(uname -i) --arch=noarch --gpgcheck \
       --download-path /var/repos/microshift-local \
       --repo=rhocp-4.12-for-rhel-8-$(uname -i)-rpms \
       --repo=fast-datapath-for-rhel-8-$(uname -i)-rpms

4. Remove coreos packages to avoid conflicts by running the following command:

   $ sudo find ${REPO_PATH}/microshift-local -name \*coreos\* -exec rm -f {} \;

5. Create a local RPM repository by running the following command:

   $ sudo createrepo ${REPO_PATH}/microshift-local

6. Create an Image Builder source file for this repository by running the following command:

   $ sudo tee ${REPO_PATH}/microshift-local/microshift.toml > /dev/null <<EOF
   id = "microshift-local"
   name = "MicroShift local repo"
   type = "yum-baseurl"
   url = "file:///${REPO_PATH}/microshift-local/"
   check_gpg = false
   check_ssl = false
   system = false
   EOF

7. Add this source file to Image Builder by running the following command:

   $ sudo composer-cli sources add ${REPO_PATH}/microshift-local/microshift.toml

Prerequisites

1. You have created an RHEL for Edge Installer (ISO) image containing your RHEL for Edge commit with Red Hat build of MicroShift.

2. Create a Kickstart file or use an existing one. In the Kickstart file, you must include:

   1. Detailed instructions about how to create a user.
   2. How to fetch and deploy the RHEL for Edge image.

Procedure

1. In the main section of the Kickstart file, update the setup of the filesystem such that it contains an LVM volume group called rhel with at least 10GB system root. Leave free space for the LVMS CSI driver to use for storing the data for your workloads.

   Example kickstart snippet for configuring the filesystem

   # Partition disk such that it contains an LVM volume group called `rhel` with a
   # 10GB+ system root but leaving free space for the LVMS CSI driver for storing data.
   #
   # For example, a 20GB disk would be partitioned in the following way:
   #
   # NAME          MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
   # sda             8:0    0  20G  0 disk
   # ├─sda1          8:1    0 200M  0 part /boot/efi
   # ├─sda1          8:1    0 800M  0 part /boot
   # └─sda2          8:2    0  19G  0 part
   #  └─rhel-root  253:0    0  10G  0 lvm  /sysroot
   #
   zerombr
   clearpart --all --initlabel
   part /boot/efi --fstype=efi --size=200
   part /boot --fstype=xfs --asprimary --size=800
   # Uncomment this line to add a SWAP partition of the recommended size
   #part swap --fstype=swap --recommended
   part pv.01 --grow
   volgroup rhel pv.01
   logvol / --vgname=rhel --fstype=xfs --size=10000 --name=root

2. In the %post section of the Kickstart file, add your pull secret and the mandatory firewall rules.

   Example Kickstart snippet for adding the pull secret and firewall rules

   %post --log=/var/log/anaconda/post-install.log --erroronfail
   
   # Add the pull secret to CRI-O and set root user-only read/write permissions
   cat > /etc/crio/openshift-pull-secret << EOF
   YOUR_OPENSHIFT_PULL_SECRET_HERE
   EOF
   chmod 600 /etc/crio/openshift-pull-secret
   
   # Configure the firewall with the mandatory rules for MicroShift
   firewall-offline-cmd --zone=trusted --add-source=10.42.0.0/16
   firewall-offline-cmd --zone=trusted --add-source=169.254.169.1
   
   %end

3. Install the mkksiso tool by running the following command:

   $ sudo yum install -y lorax

4. Update the Kickstart file in the ISO with your new Kickstart file by running the following command:

   $ sudo mkksiso <your_kickstart>.ks <your_installer>.iso <updated_installer>.iso