# Preparing the execution environment for RHOCP worker node

Prerequisites:

RedHat Enterprise Linux 8.9 must be installed and registered (opens new window) on your host machine
Configure BOND

Setting up RHEL 8.9 installer machine

This section assumes the following considerations for our deployment environment:

A server running Red Hat Enterprise Linux (RHEL) 8.9 exists within the deployment environment and is accessible to the installation user to be used as an installer machine. This server must have internet connectivity.
A virtual machine is used to act as an installer machine and the same host is utilized as an Ansible Engine host. We are using one of the worker machines as an installer machine to execute Ansible Playbook.

Prerequisites to execute ansible playbook:

RHEL 8.9 installer machine must have the following configurations:

The installer machine must have at least 500 GB disk space (especially in the "/" partition), 4 CPU cores and 16 GB RAM.
RHEL 8.9 installer machine must be subscribed with valid Red Hat credentials. To register the installer machine for the Red Hat subscription, run the following command:

$ sudo subscription-manager register --username=<username> --password=<password> --auto-attach

Sync time with NTP server.
SSH key pair must be available on the installer machine. If the SSH key is not available, generate a new SSH key pair with the following command:

$ ssh-keygen

To set up the installer machine:

Create and activate a Python3 virtual environment for deploying this solution with the following commands:

$ python3 -m venv <virtual_environment_name> 

$ source <virtual_environment_name>/bin/activate

Download the OpenShift repositories using the following commands in the Ansible Engine:

$ mkdir /opt 

$ cd /opt 

$ yum install -y git 

$ git clone <https://github.com/HewlettPackard/hpe-solutions-openshift.git>

Setup the installer machine to configure the nginx, development tools, and other python packages required for LTI installation. Navigate to the $BASE_DIR directory and run the following command:

$ cd $BASE_DIR
$ sh setup.sh

Note

$BASE_DIR refers to /opt/hpe-solutions-openshift/DL-LTI-Openshift/

As part of setup.sh script it will create nginx service, so user must download and copy Rhel 8.9 DVD ISO to /usr/share/nginx/html/
Minimum Storage requirement for management servers

Management Servers	Host OS disk	Storage Pool disk
Server 1	2 x 1.6 TB	2 x 1.6 TB
Server 2	2 x 1.6 TB	2 x 1.6 TB
Server 3	2 x 1.6 TB	2 x 1.6 TB

Host OS disk – raid1 for redundancy

Creating and deleting logical drives

Create and delete logical drives on the head nodes following below steps.

Input File Update:-

User has to update the input.yaml file in $BASE_DIR/create_delete_logicaldrives directory to execute the logical drive script.
User needs to update all the details in the input.yaml file which include:-


		ILOServers:

			- ILOIP: 172.28.*.*

				ILOuser: admin

				ILOPassword: Password

				controller: 12  

				RAID: Raid1

				PhysicalDrives: 1I:1:1,1I:1:2  

			- ILOIP: 172.28.*.*

				ILOuser: admin

				ILOPassword: Password

				controller: 1

				RAID: Raid1

				PhysicalDrives: 1I:3:1,1I:3:2

			- ILOIP: 172.28.*.*

				ILOuser: admin

				ILOPassword: Password

				controller: 11

				RAID: Raid1

				PhysicalDrives: 1I:3:1,1I:3:2

Note:-

1. To find controller id login to the respective ILO -> System Information -> Storage tab where inside Location find the **slot number** as the controller id. 

			 # Example - Slot = 12 

2. To find the PhysicalDrives login to the respective ILO -> System Information -> Storage tab inside Unconfigured Drives where under Location you can deduce PhysicalDrives based on these information:

		 # Slot: 12:Port=1I:Box=1:Bay=1

		# Example - 1I:1:1 ('Port:Box:Bay')

		# Slot: 12:Port=1I:Box=1:Bay=2

		# Example - 1I:1:2 ('Port:Box:Bay')

Playbook Execution:-

To delete all the existing logical drives in the server in case if any and to create new logical drives named 'RHEL Boot Volume' in respective ILO servers run the site.yml playbook inside create_delete_logicaldrives directory with the below mentioned command

	$ ansible-playbook site.yml --ask-vault-pass

We can provide the input variables in any one of the below methods

Method 1. Input.py : Automation way of taking input

Through the input.py, go to the directory /opt/hpe-solutions-openshift/DL-LTI-Openshift/ and run the below command.

   python input.py

Here it will prompt for values which are not obtained from SCID json files.

A sample input collection through input.py is as follows.

	Enter server serial number for the first head node server ( Example: 2M2210020X )
	2M205107TH
	Enter ILO address for the first head node server ( Example: 192.28.201.5 )
	172.28.201.13
	Enter ILO username for the first head node server ( Example: admin )
	admin
	Enter ILO password for the first head node server ( Example: Password )
	Password
	Enter Host FQDN for the first head node server ( Example: kvm1.xyz.local )
	headnode1.isv.local
	etc ...............................'

After execution of input.py, it will generate input.yaml and hosts file in the same location.

Method 2. Input.yaml: Manually editing input file

Go to the directory $BASE_DIR(/opt/hpe-solutions-openshift/DL-LTI-Openshift/), here we will have input.yaml and hosts files.

A preconfigured Ansible vault file (input.yaml) is provided as a part of this solution, which consists of sensitive information to support the host and virtual machine deployment.

cd $BASE_DIR

Run the following commands on the installer VM to edit the vault to match the installation environment.

ansible-vault edit input.yaml

NOTE

The default password for the Ansible vault file is changeme

Sample input_sample.yml can be found in the $BASE_DIR along with description of each input variable.

A sample input.yaml file is as follows with a few filled parameters.

 - Server_serial_number: 2M20510XXX
   ILO_Address: 172.28.*.*
   ILO_Username: admin
   ILO_Password: *****
   Hostname: headnode3.XX.XX                #ex. headnode3.isv.local
   Host_Username: root
   Host_Password: ******
   HWADDR1: XX:XX:XX:XX:XX:XX             #mac address for server physical interface1 
   HWADDR2: XX:XX:XX:XX:XX:XX             #mac address for server physical interface2
   Host_OS_disk: sda
   Host_VlanID: 230
   Host_IP: 172.28.*.*
   Host_Netmask: 255.*.*.*
   Host_Prefix: XX                          #ex. 8,24,32
   Host_Gateway: 172.28.*.*
   Host_DNS: 172.28.*.*
   Host_Domain: XX.XX                       #ex. isv.local
   corporate_proxy: 172.28.*.*              #provide corporate proxy, ex. proxy.houston.hpecorp.net
   corporate_proxy_port: XX               #corporate proxy port no, ex. 8080

config:
   HTTP_server_base_url: http://172.28.*.*/  #Installer IP address
   HTTP_file_path: /usr/share/nginx/html/    
   OS_type: rhel8
   OS_image_name: rhel-8.9-x86_64-dvd.iso    # ISO image should be present in /usr/share/nginx/html/
   base_kickstart_filepath: /opt/hpe-solutions-openshift/DL-LTI-Openshift/playbooks/roles/rhel8_os_deployment/tasks/ks_rhel8.cfg

A sample hosts files is as follows

		   '[kvm_nodes]
			172.28.*.*
			172.28.*.*
			172.28.*.*

			[ansible_host]
			172.28.*.*

			[rhel8_installerVM]
			172.28.*.*

			[binddns_masters]
			172.28.*.*

			[binddns_slaves]
			172.28.*.*
			172.28.*.*

			[masters_info]
			master1 ip=172.28.*.* hostname=headnode1

			[slaves_info]
			slave1 ip=172.28.*.* hostname=headnode2
			slave2 ip=172.28.*.* hostname=headnode3'

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