RHEL 8 using Podmanedit

This section provides guidelines and recommendations to install RHEL 8 and Podman. The recommended approach consists of two (2) high-level steps.

Step 1: Create a RHEL 8 instance (the version must be >= 8.5, but <9).

Step 2: Configure and prepare the new RHEL 8 instance.

When copy-pasting commands, verify that characters like quotes (“) are encoded correctly in the console where you copy the command to.

Steps that run commands starting with sudo can be run as any sudoers user. Otherwise, the corresponding user is mentioned as part of the step description.

  1. Create a RHEL 8 instance

    1. Follow your internal guidelines to add a vanilla RHEL 8 instance to your environment. Note that the version must be >= 8.5, but <9.
    2. Verify that required traffic is allowed.
  2. Configure the RHEL 8 Host

    1. Install the OS packages lvm2, iptables, sysstat, and net-tools by executing

      sudo dnf install lvm2 iptables sysstat net-tools 

      The ECE diagnostic script requires net-tools.

    2. Remove docker and previously installed podman packages (if previously installed)

      sudo dnf remove docker docker-ce podman podman-remote
    3. As a sudoers user, disable SELinux by adding the following parameter to /etc/selinux/config

    4. Install podman version 4.2.*.

      sudo dnf install podman-4.2.* podman-remote-4.2.*
    5. If podman requires a proxy in your infrastructure setup, modify the /usr/share/containers/containers.conf file and add the HTTP_PROXY and HTTPS_PROXY environment variables in the [engine] section. Please note that multiple env variables in that configuration file exists — use the one in the [engine] section.


      env = ["HTTP_PROXY=http://{proxy-ip}:{proxy-port}", "HTTPS_PROXY=http://{proxy-ip}:{proxy-port}"]
    6. Reload systemd configuration

      sudo systemctl daemon-reload
    7. Create OS groups, if they do not exist yet

      Reference: Users and permissions

      sudo groupadd elastic
      sudo groupadd podman
    8. Add user elastic to the podman group

      Reference: Users and permissions

      sudo useradd -g "elastic" -G "podman" elastic
    9. As a sudoers user, add the following line to /etc/sudoers.d/99-ece-users

      Reference: Users and permissions

      elastic ALL=(ALL) NOPASSWD:ALL
    10. Add the required options to the kernel boot arguments

      sudo /sbin/grubby --update-kernel=ALL --args='cgroup_enable=memory cgroup.memory=nokmem swapaccount=1'
    11. Create the directory

      sudo mkdir -p /etc/systemd/system/podman.socket.d
    12. As a sudoers user, create the file /etc/systemd/system/podman.socket.d/podman.conf with the following content. Set the correct ownership and permission.

      Both ListenStream= and ListenStream=/var/run/docker.sock parameters are required!

      File content:


      File ownership and permission:

      sudo chown root:root /etc/systemd/system/podman.socket.d/podman.conf
      sudo chmod 0644 /etc/systemd/system/podman.socket.d/podman.conf
    13. As a sudoers user, create the (text) file /usr/bin/docker with the following content. Verify that the regular double quotes in the text file are used (ASCII code Hex 22)

      podman-remote --url unix:///var/run/docker.sock "$@"
    14. Set the file permissions on /usr/bin/docker

      sudo chmod 0755 /usr/bin/docker
    15. As a sudoers user, add the following two lines to section [storage] in the file /etc/containers/storage.conf. Verify that those parameters are only defined once. Either remove or comment out potentially existing parameters.

      runroot = "/mnt/data/docker/runroot/"
      graphroot = "/mnt/data/docker"
    16. Enable podman so that itself and running containers start automatically after a reboot

      sudo systemctl enable podman.service
      sudo systemctl enable podman-restart.service
    17. Enable the overlay kernel module (check Use the OverlayFS storage driver) that the Podman overlay storage driver uses (check Working with the Container Storage library and tools in Red Hat Enterprise Linux).

      In Docker world there are two overlay drivers, overlay and overlay2, today most users use the overlay2 driver, so we just use that one, and called it overlay.

      -- https://docs.docker.com/storage/storagedriver/overlayfs-driver/
      echo "overlay" | sudo tee -a /etc/modules-load.d/overlay.conf
    18. Format the additional data partition

      sudo mkfs.xfs /dev/nvme1n1
    19. Create the /mnt/data/ directory used as a mount point

      sudo install -o elastic -g elastic -d -m 700 /mnt/data
    20. As a sudoers user, modify the entry for the XFS volume in the /etc/fstab file to add pquota,prjquota. The default filesystem path used by Elastic Cloud Enterprise is /mnt/data.

      Replace /dev/nvme1n1 in the following example with the corresponding device on your host, and add this example configuration as a single line to /etc/fstab.

      /dev/nvme1n1	/mnt/data	xfs	defaults,nofail,x-systemd.automount,prjquota,pquota  0 2
    21. Restart the local-fs target

      sudo systemctl daemon-reload
      sudo systemctl restart local-fs.target
    22. Set the permissions on the newly mounted device

      ls /mnt/data
      sudo chown elastic:elastic /mnt/data
    23. Create the /mnt/data/docker directory for the Docker service storage

      sudo install -o elastic -g elastic -d -m 700 /mnt/data/docker
    24. Disable the firewalld service. The service is not compatible with Podman and interferes with the installation of ECE. You must disable firewalld before installing or reinstalling ECE.

      If firewalld does not exist on your VM, you can skip this step.

      sudo systemctl disable firewalld
    25. Configure kernel parameters

      cat <<EOF | sudo tee -a /etc/sysctl.conf
      # Required by Elasticsearch 5.0 and later
      # enable forwarding so the Docker networking works as expected
      # Decrease the maximum number of TCP retransmissions to 5 as recommended for Elasticsearch TCP retransmission timeout.
      # See https://www.elastic.co/guide/en/elasticsearch/reference/current/system-config-tcpretries.html
      # Make sure the host doesn't swap too early
    26. Apply the new sysctl settings

      sudo sysctl -p
      sudo systemctl restart NetworkManager
    27. As a sudoers user, adjust the system limits. Add the following configuration values to the /etc/security/limits.conf file.

      *                soft    nofile         1024000
      *                hard    nofile         1024000
      *                soft    memlock        unlimited
      *                hard    memlock        unlimited
      elastic          soft    nofile         1024000
      elastic          hard    nofile         1024000
      elastic          soft    memlock        unlimited
      elastic          hard    memlock        unlimited
      root             soft    nofile         1024000
      root             hard    nofile         1024000
      root             soft    memlock        unlimited
    28. Authenticate the elastic user to pull images from the docker registry you use, by creating the file /home/elastic/.docker/config.json. This file needs to be owned by the elastic user. If you are using a user name other than elastic, adjust the path accordingly.

      Example: In case you use docker.elastic.co, the file content looks like as follows:

       "auths": {
         "docker.elastic.co": {
           "auth": "<auth-token>"
    29. Restart the podman service by running this command:

      sudo systemctl daemon-reload
      sudo systemctl restart podman
    30. Reboot the RHEL host

      sudo reboot