Set up the management and compute node

Set up supported RHEL operating system to prepare for the management and each compute node, the following description uses RHEL8:

Setting up RHEL8 operating system

Before you install the IBM® Cloud Infrastructure Center, you must install Red Hat Enterprise Linux 8.4 or Red Hat Enterprise Linux 8.6 into the management node and each compute node. For hardware requirements, see Hardware and software requirements.

For detailed Red Hat Enterprise Linux installation instructions, see the documentation in the Red Hat Customer Portal.

Note: RHEL8 system which is in-place upgraded from RHEL7 is not supported by the IBM Cloud Infrastructure Center, see the documentation in In-place upgrade paths for Red Hat Enterprise Linux

Enable auto restart of RHEL8 operating system

The z/VM® or KVM hypervisor may restart at some unexpected situation, each RHEL8 operation system needs to enable auto restart after the hypervisor is restarted.

For z/VM hypervisor, set the operating system to starting and stopping automatically with z/VM system, see the documentation in Starting and stopping virtual machines automatically.

Run a test with hypervisor restarting to verify the RHEL8 operating systems can automatically be restarted is recommended.

Additional configuration

Configure YUM Repository

IBM Cloud Infrastructure Center requires certain packages to be installed. Configure and enable the Red Hat Enterprise Linux yum or dnf repository on the server by using RHN or RHSM. This allows IBM Cloud Infrastructure Center to find and install the required packages during installation. For Red Hat Enterprise Linux 8.2, some of the prerequisites for installing IBM Cloud Infrastructure Center require BaseOS and AppStream repositories. To avoid a conflict, ensure all the other repositories are disabled or removed except for the BaseOS and AppStream repositories.

For more information, refer to DISTRIBUTION OF CONTENT IN RHEL 8, 3.2 Repositories in RHEL's documentation.

Install tar on Compute node and Management node if needed

Installing IBM Cloud Infrastructure Center on management node and performing add host for compute node requires both tar and psmisc programs on both management node and compute node. You need to install missing program if any node lacks any program. Install tar with following command.

sudo dnf install tar

Install psmisc with following command.

sudo dnf install psmisc

(Optional) configure non-root user on compute node if needed

IBM Cloud Infrastructure Center can directly add host as the compute node by root user of the host. If you need to add host by non-root user of the host, you shall take the steps beneath on the host before adding it as the compute node. If you already have a non-root user on the host, you can skip the following steps 1 - 3.

  1. Run the command to create user:

    adduser <user_name>

    The <user_name> is the new user name you want to create and will be used to add host.

  2. Run the command to set user password if needed:

    passwd <user_name>
  3. Add other configurations like home directory if needed.

  4. Grant the user <user_name> the privileges to run commands and open files without password as a root user or administrator, you need open file /etc/sudoers with root access and add one new line <user_name> ALL=(ALL) NOPASSWD: ALL under the part ## Allow root to run any commands anywhere, for example:

    ## Allow root to run any commands anywhere
    root    ALL=(ALL)       ALL
    <user_name> ALL=(ALL)     NOPASSWD: ALL
  5. Open file /etc/sudoers and comment out configure line Defaults requiretty if it exists.

    # Defaults    requiretty

    Note: This is very important for adding host with a non-root user. If this line exists in /etc/sudoers and is not commented out, the non-root user can not run any sudo command and adding host fails.

  6. Verify the user <user_name> has the privileges to run commands and open files without password as a root user. For example, you can input the following commands to access the directory /root without password:

    su - <user_name>
    sudo ls /root