To install Red Hat Enterprise Linux 8.0 in the CSAH node:
- Follow the guidelines in Red Hat Enterprise Linux 8.0 Installation.
The Red Hat Enterprise Linux Installation UI is displayed, as shown in the following figure:
Figure 1. Operating system installation UI options
Note: Under Software Selection, ensure that Server with GUI is selected.
- Run the following tasks as user ‘root’ unless directed otherwise.
After the installation is complete, set the hostname to reflect the naming standards by running the following command:
hostnamectl set-hostname <hostname>.<clustername>.<base domain>
hostnamectl set-hostname csah.ocp.example.com
- Assign an IP address to the interface. As part of our validation, we used interface ens2f0.
nmcli connection modify ens2f0 ipv4.method manual ipv4.address <ipaddress/cidr> connection.autoconnect yes ipv4.gateway <gateway> ipv4.dns <dns-server> ipv4.dns-search <clustername.base domain>
Note: The assigned IP address must be able to reach the internet and the DNS must be able to resolve subscription.rhsm.redhat.com. For this installation process, internet access for all nodes is required. Red Hat provides an offline deployment method that is beyond the scope of this deployment guide.
- Add the newly created hostname in the /etc/hosts file along with its IP address, as shown in the following command:
100.82.46.20 csah csah.ocp.example.com
- Enable the ansible-2.8-for-rhel-8-x86_64-rpms repository by using subscription-manager as follows:
subscription-manager register --username <subscription.user> --password <subscription.password> --force
subscription-manager attach --pool=<pool id>
subscription-manager repos --enable=ansible-2.8-for-rhel-8-x86_64-rpms
- Install the following rpms:
yum install -y git jq ansible
- Create a user to run playbooks by running the following command:
Note: Do not use ‘core’ as the username. User core is used as part of the OpenShift Container Platform cluster configuration. The remainder of this guide assumes that user ‘ansible’ is created to run playbooks.
- Set up password-less access to the CSAH FQDN. As user ansible, run the following commands:
ssh-keygen (press enter and go by defaults for the next set of questions)
cat .ssh/id_rsa.pub > .ssh/authorized_keys
chmod 600 .ssh/authorized_keys
- As root, provide permissions to the user that you have just created to run all commands without being prompted for a password. The content in bold provides a reference.
# add the following line after # %wheel ALL=(ALL) NOPASSWD: ALL
ansible ALL=(ALL) NOPASSWD: ALL
- As user ansible, download the Ansible playbooks from GitHub by running the following command: