Overview

When deployed on OpenStack, OKD can be configured to access the OpenStack infrastructure, including using OpenStack Cinder volumes as persistent storage for application data.

Before you Begin

OKD Prerequisites

A successful deployment of OKD requires many prerequisites. This consists of a set of infrastructure and host configuration steps prior to the actual installation of OKD using Ansible. In the following subsequent sections, details regarding the prerequisites and configuration changes required for an OKD on a OpenStack environment are discussed in detail.

All the OpenStack CLI commands in this reference environment are executed using the CLI openstack commands within the OpenStack director node. If using a workstation or laptop to execute these commands instead of the OpenStack director node, please ensure to install the following packages found within the specified repositories.

Example:

Enable the rhel-7-server-openstack-13-rpms and the required OKD repositories from Set Up Repositories.

$ sudo subscription-manager repos \
--enable rhel-7-server-openstack-13-rpms
$ sudo yum install -y python2-openstackclient python2-heatclient python2-octaviaclient ansible

Verify the packages are of at least the following versions (use rpm -q <package_name>):

  • python2-openstackclient - 3.14.1.-1

  • python2-heatclient 1.14.0-1

  • python2-octaviaclient 1.4.0-1

  • ansible > 2.4.3

Enabling Octavia: OpenStack Load Balancing as a Service (LBaaS)

Octavia is a supported load balancer solution that is recommended to be used in conjunction with OKD in order to load balance the external incoming traffic and provide a single view of the OKD master services for the applications.

In order to enable Octavia, the Octavia service must be included during the installation of the OpenStack overcloud or upgraded if the overcloud already exists. The following steps provide basic non-custom steps in enabling Octavia and apply to both either a clean install of the overcloud or an overcloud update.

The following steps only capture the key pieces required during the deployment of OpenStack when dealing with Octavia. For more information visit the documentation of Installation of OpenStack. It is also important to note that registry methods vary. For more information visit the documentation on Registry Methods. This example used the local registry method.

If using the local registry, create a template to upload the images to the registry. Example shown below.

(undercloud) $ openstack overcloud container image prepare \
-e /usr/share/openstack-tripleo-heat-templates/environments/services-docker/octavia.yaml \
--namespace=registry.access.redhat.com/rhosp13 \
--push-destination=<local-ip-from-undercloud.conf>:8787 \
--prefix=openstack- \
--tag-from-label {version}-{release} \
--output-env-file=/home/stack/templates/overcloud_images.yaml \
--output-images-file /home/stack/local_registry_images.yaml

Verify that the created local_registry_images.yaml contains the Octavia images.

Octavia images in local registry file
...
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-api:13.0-43
  push_destination: <local-ip-from-undercloud.conf>:8787
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-health-manager:13.0-45
  push_destination: <local-ip-from-undercloud.conf>:8787
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-housekeeping:13.0-45
  push_destination: <local-ip-from-undercloud.conf>:8787
- imagename: registry.access.redhat.com/rhosp13/openstack-octavia-worker:13.0-44
  push_destination: <local-ip-from-undercloud.conf>:8787
...

The following step pulls the container images from registry.access.redhat.com to the undercloud node. This may take soem time depending on the speed of the network and undercloud disk.

(undercloud) $ sudo openstack overcloud container image upload \
  --config-file  /home/stack/local_registry_images.yaml \
  --verbose

Install or update your overcloud environment with Octavia:

openstack overcloud deploy --templates \
.
.
.
  -e /usr/share/openstack-tripleo-heat-templates/environments/services-docker/octavia.yaml \
.
.
.
The command above only includes the files associated with Octavia. This command will vary based upon your specifc installation of OpenStack. See the official OpenStack documentation for further information. For more information on customizing your Octavia installation, see installation of Octavia using Director.
Creating OpenStack User Accounts, Projects and Roles

Before installing OKD, the Red Hat OpenStack Platform (RHOSP) environment requires a project, often referred to as a tenant, that stores the OpenStack instances that are to install the OKD. This project requires ownership by a user and role of that user to be set to _member_.

The following steps show how to accomplish the above.

As the OpenStack overcloud administrator,

  1. Create a project (tenant) that is to store the RHOSP instances

    $ openstack project create <project>
  2. Create a RHOSP user that has ownership of the previously created project:

    $ openstack user create --password <password> <username>
  3. Set the role of the user:

    $ openstack role add --user <username> --project <project> _member_

Once the above is complete, an OpenStack administrator can create an RC file with all the required information to the user(s) implementing the OKD environment.

An example RC file:

$ cat path/to/examplerc
# Clear any old environment that may conflict.
for key in $( set | awk '{FS="="}  /^OS_/ {print $1}' ); do unset $key ; done
export OS_PROJECT_DOMAIN_NAME=Default
export OS_USER_DOMAIN_NAME=Default
export OS_PROJECT_NAME=<project-name>
export OS_USERNAME=<username>
export OS_PASSWORD=<password>
export OS_AUTH_URL=http://<ip>:5000//v3
export OS_CLOUDNAME=<cloud-name>
export OS_IDENTITY_API_VERSION=3

# Add OS_CLOUDNAME to PS1
if [ -z "${CLOUDPROMPT_ENABLED:-}" ]; then
	export PS1=${PS1:-""}
	export PS1=\${OS_CLOUDNAME:+"(\$OS_CLOUDNAME)"}\ $PS1
	export CLOUDPROMPT_ENABLED=1
fi

As the user(s) implementing the OKD environment, within the OpenStack director node or workstation, ensure to source the credentials as follows:

$ source path/to/examplerc
Create an OpenStack Flavor

Within OpenStack, flavors define the size of a virtual server by defining the compute, memory, and storage capacity of nova computing instances. Since the base image within this reference architecture is Red Hat Enterprise Linux 7.5, a m1.node and m1.master sized flavor is created with the following specifications as shown in Minimum System Requirements for OpenShift.

Table 1. Minimum System Requirements for OpenShift
Node Type CPU RAM Root Disk Flavor

Masters

4*

16** GB

45 GB

m1.master

Nodes

1

8 GB

20 GB

m1.node

\* Additional vCPU is recommended.

\\** Additional memory is recommended if etcd is co-located on masters.

As an OpenStack administrator,

$ openstack flavor create <flavor_name> \
    --id auto \
    --ram <ram_in_MB> \
    --disk <disk_in_GB> \
    --vcpus <num_vcpus>

An example below showing the creation of flavors within this reference environment.

$ openstack flavor create m1.master \
    --id auto \
    --ram 16384 \
    --disk 45 \
    --vcpus 4
$ openstack flavor create m1.node \
    --id auto \
    --ram 8192 \
    --disk 20 \
    --vcpus 1
If access to OpenStack administrator privileges to create new flavors is unavailable, use existing flavors within the OpenStack environment that meet the requirements in Minimum System Requirements for OpenShift.

Verification of the OpenStack flavors via:

$ openstack flavor list
Creating an OpenStack Keypair

Red Hat OpenStack Platform uses cloud-init to place an ssh public key on each instance as it is created to allow ssh access to the instance. Red Hat OpenStack Platform expects the user to hold the private key.

Losing the private key will cause the inability to access the instances.

To generate a keypair, use the following command:

$ openstack keypair create <keypair-name> > /path/to/<keypair-name>.pem

Verification of the keypair creation can be done via:

$ openstack keypair list

Once the keypair is created, set the permissions to 600 thus only allowing the owner of the file to read and write to that file.

$ chmod 600 /path/to/<keypair-name>.pem
Setting up DNS for OKD

DNS service is an important component in the OKD environment. Regardless of the provider of DNS, an organization is required to have certain records in place to serve the various OKD components.

Using /etc/hosts is not valid, a proper DNS service must exist.

Using the key secret of the DNS, you can provide the information to the OpenShift Ansible Installer and it will automatically add A records for the target instances and the various OKD components. This process setup is described later when configuring the OpenShift Ansible Installer.

Access to a DNS server is expected. You can use Red Hat Labs DNS Helper for assistance with access.

Application DNS

Applications served by OpenShift are accessible by the router on ports 80/TCP and 443/TCP. The router uses a wildcard record to map all host names under a specific sub domain to the same IP address without requiring a separate record for each name.

This allows OKD to add applications with arbitrary names as long as they are under that sub domain.

For example, a wildcard record for *.apps.example.com causes DNS name lookups for tax.apps.example.com and home-goods.apps.example.com to both return the same IP address: 10.19.x.y. All traffic is forwarded to the OpenShift Routers. The Routers examine the HTTP headers of the queries and forward them to the correct destination.

With a load-balancer such as Octavia, host address of 10.19.x.y, the wildcard DNS record can be added as follows:

Table 2. Load Balancer DNS records
IP Address Hostname Purpose

10.19.x.y

*.apps.example.com

User access to application web services

Creation of OKD Networks via OpenStack

When deploying OKD on Red Hat OpenStack Platform as described in this segment, the requirements are two networks — public and internal network.

Public Network

The public network is a network that contains external access and can be reached by the outside world. The public network creation can be only done by an OpenStack administrator.

The following commands provide an example of creating an OpenStack provider network for public network access.

As an OpenStack administrator (overcloudrc access),

$ source /path/to/examplerc

$ openstack network create <public-net-name> \
  --external \
  --provider-network-type flat \
  --provider-physical-network datacentre

$ openstack subnet create <public-subnet-name> \
  --network <public-net-name> \
  --dhcp \
  --allocation-pool start=<float_start_ip>,end=<float_end_ip> \
  --gateway <ip> \
  --subnet-range <CIDR>

Once the network and subnet have been created verify via:

$ openstack network list
$ openstack subnet list

<float_start_ip> and <float_end_ip> are the associated floating IP pool provided to the network labeled public network. The Classless Inter-Domain Routing (CIDR) uses the format <ip>/<routing_prefix>, i.e. 10.0.0.1/24.

Internal Network

The internal network is connected to the public network via a router during the network setup. This allows each Red Hat OpenStack Platform instance attached to the internal network the ability to request a floating IP from the public network for public access. The internal network is created automically by the OpenShift Ansible installer via setting the openshift_openstack_private_network_name. More information regarding changes required for the OpenShift Ansible installer are described later.

Creating OpenStack Deployment Host Security Group

OpenStack networking allows the user to define inbound and outbound traffic filters that can be applied to each instance on a network. This allows the user to limit network traffic to each instance based on the function of the instance services and not depend on host based filtering. The OpenShift Ansible installer handles the proper creation of all the ports and services required for each type of host that is part of the OKD cluster except for the deployment host.

The following command creates an empty security group with no rules set for the deployment host.

$ source path/to/examplerc
$ openstack security group create <deployment-sg-name>

Verify the creation of the security group:

$ openstack security group list

Deployment Host Security Group

The deployment instance only needs to allow inbound ssh. This instance exists to give operators a stable base to deploy, monitor and manage the OKD environment.

Table 3. Deployment Host Security Group TCP ports
Port/Protocol Service Remote source Purpose

ICMP

ICMP

Any

Allow ping, traceroute, etc.

22/TCP

SSH

Any

Secure shell login

Creation of the above security group rules is as follows:

$ source /path/to/examplerc
$ openstack security group rule create \
    --ingress \
    --protocol icmp \
    <deployment-sg-name>
$ openstack security group rule create \
    --ingress \
    --protocol tcp \
    --dst-port 22 \
    <deployment-sg-name>

Verification of the security group rules is as follows:

$ openstack security group rule list <deployment-sg-name>
+--------------------------------------+-------------+-----------+------------+-----------------------+
| ID                                   | IP Protocol | IP Range  | Port Range | Remote Security Group |
+--------------------------------------+-------------+-----------+------------+-----------------------+
| 7971fc03-4bfe-4153-8bde-5ae0f93e94a8 | icmp        | 0.0.0.0/0 |            | None                  |
| b8508884-e82b-4ee3-9f36-f57e1803e4a4 | None        | None      |            | None                  |
| cb914caf-3e84-48e2-8a01-c23e61855bf6 | tcp         | 0.0.0.0/0 | 22:22      | None                  |
| e8764c02-526e-453f-b978-c5ea757c3ac5 | None        | None      |            | None                  |
+--------------------------------------+-------------+-----------+------------+-----------------------+
OpenStack Cinder Volumes

OpenStack Block Storage provides persistent block storage management via the cinder service. Block storage enables the OpenStack user to create a volume that may be attached to different OpenStack instances.

Docker Volume

The master and node instances contain a volume to store docker images. The purpose of the volume is to ensure that a large image or container does not compromise node performance or abilities of the existing node.

A docker volume of a minimum of 15GB is required for running containers. This may need adjustment depending on the size and number of containers each node will run.

The docker volume is created by the OpenShift Ansible installer via the variable openshift_openstack_docker_volume_size. More information regarding changes required for the OpenShift Ansible installer are described later.

Registry volume

The OpenShift image registry requires a cinder volume to ensure that images are saved in the event that the registry needs to migrate to another node. The following steps show how to create the image registry via OpenStack. Once the volume is created, the volume ID will be included in the OpenShift Ansible Installer OSEv3.yml file via the parameter openshift_hosted_registry_storage_openstack_volumeID as described later.

$ source /path/to/examplerc
$ openstack volume create --size <volume-size-in-GB> <registry-name>
The registry volume size should be at least 30GB.

Verify the creation of the volume.

$ openstack volume list
----------------------------------------+------------------------------------------------+
| ID                                   | Name          | Status    | Size | Attached to  |
+--------------------------------------+-------------------------------------------------+
| d65209f0-9061-4cd8-8827-ae6e2253a18d | <regisry-name>| available |   30 |              |
+--------------------------------------+-------------------------------------------------+
Creating and Configuring the Deployment Instance

The role of the deployment instance is to serve as a utility host for the deployment and management of OKD.

Creating the Deployment Host Network and Router

Prior to instance creation, an internal network and router must be created for communication with the deployment host. The following commands create that network and router.

$ source path/to/examplerc

$ openstack network create <deployment-net-name>

$ openstack subnet create --network <deployment-net-name> \
  --subnet-range <subnet_range> \
  --dns-nameserver <dns-ip> \
  <deployment-subnet-name>

$ openstack router create <deployment-router-name>

$ openstack router set --external-gateway <public-net-name> <deployment-router-name>

$ openstack router add subnet <deployment-router-name> <deployment-subnet-name>

Deploying the Deployment Instance

With the network and security group created, deploy the instance.

$ domain=<domain>
$ netid1=$(openstack network show <deployment-net-name> -f value -c id)
$ openstack server create \
    --nic net-id=$netid1 \
    --flavor <flavor> \
    --image <image> \
    --key-name <keypair> \
    --security-group <deployment-sg-name> \
    deployment.$domain
If the m1.small flavor does not exist by default then use an existing flavor that meets the requirements of 1 vCPU and 2GB of RAM.

Creating and Adding Floating IP to the Deployment Instance

Once the deployment instance is created, a floating IP must be created and then allocated to the instance. The following shows an example.

$ source /path/to/examplerc
$ openstack floating ip create <public-network-name>
+---------------------+--------------------------------------+
| Field               | Value                                |
+---------------------+--------------------------------------+
| created_at          | 2017-08-24T22:44:03Z                 |
| description         |                                      |
| fixed_ip_address    | None                                 |
| floating_ip_address | 10.20.120.150                       |
| floating_network_id | 084884f9-d9d2-477a-bae7-26dbb4ff1873 |
| headers             |                                      |
| id                  | 2bc06e39-1efb-453e-8642-39f910ac8fd1 |
| port_id             | None                                 |
| project_id          | ca304dfee9a04597b16d253efd0e2332     |
| project_id          | ca304dfee9a04597b16d253efd0e2332     |
| revision_number     | 1                                    |
| router_id           | None                                 |
| status              | DOWN                                 |
| updated_at          | 2017-08-24T22:44:03Z                 |
+---------------------+--------------------------------------+

Within the above output, the floating_ip_address field shows that the floating IP 10.20.120.150 is created. In order to assign this IP to the deployment instance, run the following command:

$ source /path/to/examplerc
$ openstack server add floating ip <deployment-instance-name> <ip>

For example, if instance deployment.example.com is to be assigned IP 10.20.120.150 the command would be:

$ source /path/to/examplerc
$ openstack server add floating ip deployment.example.com 10.20.120.150

Adding the RC File to the Deployment Host

Once the deployment host exists, copy the RC file created earlier to the deployment host via scp as follows

scp <rc-file-deployment-host> cloud-user@<ip>:/home/cloud-user/
Deployment Host Configuration for OKD

The following subsections describe all the steps needed to properly configure the deployment instance.

Configure ~/.ssh/config to use Deployment Host as a Jumphost

To easily connect to the OKD environment, follow the steps below.

On the OpenStack director node or local workstation with the private key, <keypair-name>.pem:

$ exec ssh-agent bash

$ ssh-add /path/to/<keypair-name>.pem
Identity added: /path/to/<keypair-name>.pem (/path/to/<keypair-name>.pem)

Add to the ~/.ssh/config file:

Host deployment
    HostName        <deployment_fqdn_hostname OR IP address>
    User            cloud-user
    IdentityFile    /path/to/<keypair-name>.pem
    ForwardAgent     yes

ssh into the deployment host with the -A option that enables forwarding of the authentication agent connection.

Ensure the permissions are read write only for the owner of the ~/.ssh/config file:

$ chmod 600 ~/.ssh/config
$ ssh -A cloud-user@deployment

Once logged into the deployment host, verify the ssh agent forwarding is working via checking for the SSH_AUTH_SOCK

$ echo "$SSH_AUTH_SOCK"
/tmp/ssh-NDFDQD02qB/agent.1387

Subscription Manager and Enabling OKD Repositories

Within the deployment instance, register it with the Red Hat Subscription Manager. This can be accomplished by using credentials:

$ sudo subscription-manager register --username <user> --password '<password>'

Alternatively, you can use an activation key:

$ sudo subscription-manager register --org="<org_id>" --activationkey=<keyname>

Once registered, enable the following repositories as follows.

$ sudo subscription-manager repos \
    --enable="rhel-7-server-rpms" \
    --enable="rhel-7-server-extras-rpms" \
    --enable="rhel-7-server-ose-3.10-rpms" \
    --enable="rhel-7-server-ansible-2.4-rpms" \
    --enable="rhel-7-server-openstack-13-rpms" \
    --enable="rhel-7-server-openstack-13-tools-rpms"

Refer to the Set Up Repositories to confirm the proper OKD repositories and Ansible versions to enable. The above file is just a sample.

Required Packages on the Deployment Host

The following packages are required to be installed on the deployment host.

Install the following packages:

  • openshift-ansible

  • python-openstackclient

  • python2-heatclient

  • python2-octaviaclient

  • python2-shade

  • python-dns

  • git

  • ansible

$ sudo yum -y install openshift-ansible python-openstackclient python2-heatclient python2-octaviaclient python2-shade python-dns git ansible

Configure Ansible

ansible is installed on the deployment instance to perform the registration, installation of packages, and the deployment of the OKD environment on the master and node instances.

Before running playbooks, it is important to create an ansible.cfg file to reflect the environment you wish to deploy:

$ cat ~/ansible.cfg

[defaults]
forks = 20
host_key_checking = False
remote_user = openshift
gathering = smart
fact_caching = jsonfile
fact_caching_connection = $HOME/ansible/facts
fact_caching_timeout = 600
log_path = $HOME/ansible.log
nocows = 1
callback_whitelist = profile_tasks
inventory = /usr/share/ansible/openshift-ansible/playbooks/openstack/inventory.py,/home/cloud-user/inventory

[ssh_connection]
ssh_args = -o ControlMaster=auto -o ControlPersist=600s -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=false
control_path = %(directory)s/%%h-%%r
pipelining = True
timeout = 10

[persistent_connection]
connect_timeout = 30
connect_retries = 30
connect_interval = 1

The following parameters values are important to the ansible.cfg file.

  • The remote_user must remain as the user openshift.

  • The inventory parameter ensure that there is no space between the two inventories.

Example: inventory = path/to/inventory1,path/to/inventory2

The code block above can overwrite the default values in the file. Ensure to populate <keypair-name> with the keypair that was copied to the deployment instance.

The inventory folder is created in Preparing the Inventory for Provisioning.

OpenShift Authentication

OKD provides the ability to use many different authentication platforms. A listing of authentication options are available at Configuring Authentication and User Agent.

Configuring the default identity provider is important as the default configuration is to Deny All.

Provisioning OKD Instances using the OpenShift Ansible Playbooks

Once the creation and configuration of the deployment host is complete, we turn to preparing the environment for the deployment of OKD using Ansible. In the following subsections, Ansible is configured and certain YAML files are modified to achieve a successful OKD on OpenStack deployment.

Preparing the Inventory for Provisioning

With the installation of the openshift-ansible package complete via our previous steps, there resides a sample-inventory directory that we will copy to our cloud-user home directory of the deployment host.

On the deployment host,

$ cp -r /usr/share/ansible/openshift-ansible/playbooks/openstack/sample-inventory/ ~/inventory

Within this inventory directory, the all.yml file contains all the different parameters that must be set in to order to achieve successful provisioning of the RHOCP instances. The OSEv3.yml file contains some references required by the all.yml file plus all the different OpenShift cluster parameter installation customization one would want.

[[all_yml_file] ==== all.yml configuration

The all.yml has many options that can be modified to meet your specific needs. The information gathered in this file is for the provisioning portion of the instances required for a successful deployment of OKD. It is important to review these carefully. This document will provide a condensed version of the all.yml and focus on the most critical parameters that need to be set for a successful deployment.

$ cat ~/inventory/group_vars/all.yml
---
openshift_openstack_clusterid: "openshift"
openshift_openstack_public_dns_domain: "example.com"
openshift_openstack_dns_nameservers: ["10.19.115.228"]
openshift_openstack_public_hostname_suffix: "-public"
openshift_openstack_nsupdate_zone: "{{ openshift_openstack_public_dns_domain }}"

openshift_openstack_keypair_name: "openshift"
openshift_openstack_external_network_name: "public"

openshift_openstack_default_image_name: "rhel75"

openshift_openstack_num_masters: 3
openshift_openstack_num_infra: 3
openshift_openstack_num_cns: 0
openshift_openstack_num_nodes: 2

openshift_openstack_master_flavor: "m1.master"
openshift_openstack_default_flavor: "m1.node"

openshift_openstack_use_lbaas_load_balancer: true

openshift_openstack_docker_volume_size: "15"

# # Roll-your-own DNS
openshift_openstack_external_nsupdate_keys:
  public:
    key_secret: '/alb8h0EAFWvb4i+CMA12w=='
    key_name: "update-key"
    key_algorithm: 'hmac-md5'
    server: '<ip-of-DNS>'
  private:
    key_secret: '/alb8h0EAFWvb4i+CMA12w=='
    key_name: "update-key"
    key_algorithm: 'hmac-md5'
    server: '<ip-of-DNS>'

ansible_user: openshift

## cloud config
openshift_openstack_disable_root: true
openshift_openstack_user: openshift
Due to using an external DNS server, the private and public sections use the public IP address of the DNS server as the DNS server does not reside in the OpenStack environment.

The values above that are bold require modification based upon your OpenStack environment and DNS server.

In order to properly modify the DNS portion of the all.yml, login to the DNS server and perform the following commands to capture the key name, key algorithm and key secret:

$ ssh <ip-of-DNS>
$ sudo -i
# cat /etc/named/<key-name.key>
key "update-key" {
	algorithm hmac-md5;
	secret "/alb8h0EAFWvb4i+CMA02w==";
};
The key name may vary and the above is only an example.

Brief description of each variable in the table below:

Table 4. Description of Variables in all.yml
Variable Description

openshift_openstack_clusterid

Cluster identification name

openshift_openstack_public_dns_domain

Public DNS domain name

openshift_openstack_dns_nameservers

IP of DNS nameservers

openshift_openstack_public_hostname_suffix

Adds a suffix to the node hostname in the DNS record for both public and private

openshift_openstack_nsupdate_zone

Zone to be updated with OCP instance IPs

openshift_openstack_keypair_name

Keypair name used to log into OCP instances

openshift_openstack_external_network_name

OpenStack public network name

openshift_openstack_default_image_name

OpenStack image used for OCP instances

openshift_openstack_num_masters

Number of master nodes to deploy

openshift_openstack_num_infra

Number of infrastructure nodes to deploy

openshift_openstack_num_cns

Number of container native storage nodes to deploy

openshift_openstack_num_nodes

Number of application nodes to deploy

openshift_openstack_master_flavor

Name of the OpenStack flavor used for master instances

openshift_openstack_default_flavor

Name of the Openstack flavor used for all instances, if specific flavor not specified.

openshift_openstack_use_lbaas_load_balancer

Boolean value enabling Octavia load balancer (Octavia must be installed)

openshift_openstack_docker_volume_size

Minimum size of the Docker volume (required variable)

openshift_openstack_external_nsupdate_keys

Updating the DNS with the instance IP addresses

ansible_user

Ansible user used to deploy OKD. "openshift" is the required name and must not be changed.

openshift_openstack_disable_root

Boolean value that disables root access

openshift_openstack_user

OCP instances created with this user

OSEv3.yml

The OSEv3.yml file specificies all the different parameters and customizations relating the installation of OpenShift.

Below is a condensed version of the file with all required variables for a successful deployment. Additional variables may be required depending on what customization is required for your specific OKD deployment.

$ cat ~/inventory/group_vars/OSEv3.yml
---

openshift_deployment_type: openshift-enterprise
openshift_release: v3.10

openshift_master_default_subdomain: "apps.{{ (openshift_openstack_clusterid|trim == '') | ternary(openshift_openstack_public_dns_domain, openshift_openstack_clusterid + '.' + openshift_openstack_public_dns_domain) }}"

openshift_master_cluster_public_hostname: "console.{{ (openshift_openstack_clusterid|trim == '') | ternary(openshift_openstack_public_dns_domain, openshift_openstack_clusterid + '.' + openshift_openstack_public_dns_domain) }}"

OpenStack Credentials:
openshift_cloudprovider_kind: openstack
openshift_cloudprovider_openstack_auth_url: "{{ lookup('env','OS_AUTH_URL') }}"
openshift_cloudprovider_openstack_username: "{{ lookup('env','OS_USERNAME') }}"
openshift_cloudprovider_openstack_password: "{{ lookup('env','OS_PASSWORD') }}"
openshift_cloudprovider_openstack_tenant_name: "{{ lookup('env','OS_PROJECT_NAME') }}"
openshift_cloudprovider_openstack_blockstorage_version: v2
openshift_cloudprovider_openstack_domain_name: "{{ lookup('env','OS_USER_DOMAIN_NAME') }}"

# Use Cinder volume for Openshift registry:
openshift_hosted_registry_storage_kind: openstack
openshift_hosted_registry_storage_access_modes: ['ReadWriteOnce']
openshift_hosted_registry_storage_openstack_filesystem: xfs
openshift_hosted_registry_storage_volume_size: 30Gi


openshift_hosted_registry_storage_openstack_volumeID: d65209f0-9061-4cd8-8827-ae6e2253a18d
openshift_hostname_check: false
ansible_become: true

#Setting SDN (defaults to ovs-networkpolicy) not part of OSEv3.yml
#For more info, on which to choose, visit:
#https://docs.openshift.com/container-platform/3.10/architecture/networking/sdn.html#overview
networkPluginName: redhat/ovs-networkpolicy
#networkPluginName: redhat/ovs-multitenant

#Configuring identity providers with Ansible
#For initial cluster installations, the Deny All identity provider is configured
#by default. It is recommended to be configured with either htpasswd
#authentication, LDAP authentication, or Allowing all authentication (not recommended)
#For more info, visit:
#https://docs.openshift.com/container-platform/3.10/install_config/configuring_authentication.html#identity-providers-ansible
#Example of Allowing All
#openshift_master_identity_providers: [{'name': 'allow_all', 'login': 'true', 'challenge': 'true', 'kind': 'AllowAllPasswordIdentityProvider'}]


#Optional Metrics (uncomment below lines for installation)

#openshift_metrics_install_metrics: true
#openshift_metrics_cassandra_storage_type: dynamic
#openshift_metrics_storage_volume_size: 25Gi
#openshift_metrics_cassandra_nodeselector: {"node-role.kubernetes.io/infra":"true"}
#openshift_metrics_hawkular_nodeselector: {"node-role.kubernetes.io/infra":"true"}
#openshift_metrics_heapster_nodeselector: {"node-role.kubernetes.io/infra":"true"}

#Optional Aggregated Logging (uncomment below lines for installation)

#openshift_logging_install_logging: true
#openshift_logging_es_pvc_dynamic: true
#openshift_logging_es_pvc_size: 30Gi
#openshift_logging_es_cluster_size: 3
#openshift_logging_es_number_of_replicas: 1
#openshift_logging_es_nodeselector: {"node-role.kubernetes.io/infra":"true"}
#openshift_logging_kibana_nodeselector: {"node-role.kubernetes.io/infra":"true"}
#openshift_logging_curator_nodeselector: {"node-role.kubernetes.io/infra":"true"}

For further details on any of the variables listed, see an example OpenShift-Ansible host inventory.

OpenStack Prerequisites Playbook

The OKD Ansible Installer provides a playbook to ensure all the provisioning steps of the OpenStack instances have been met.

Prior to running the playbook, ensure to source the RC file

$ source path/to/examplerc

Via the ansible-playbook command on the deployment host, ensure all the prerequisites are met using prerequisites.yml playbook:

$  ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/openstack/openshift-cluster/prerequisites.yml

Once the prerequisite playbook completes successfully, run the provision playbook as follows:

$ ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/openstack/openshift-cluster/provision.yml

If provision.yml prematurely errors, check if the status of the OpenStack stack and wait for it finish

$ watch openstack stack list
+--------------------------------------+-------------------+--------------------+----------------------+--------------+
| ID                                   | Stack Name        | Stack Status       | Creation Time        | Updated Time |
+--------------------------------------+-------------------+--------------------+----------------------+--------------+
| 87cb6d1c-8516-40fc-892b-49ad5cb87fac | openshift-cluster | CREATE_IN_PROGRESS | 2018-08-20T23:44:46Z | None         |
+--------------------------------------+-------------------+--------------------+----------------------+--------------+

If the stack shows a CREATE_IN_PROGRESS, wait for the stack to complete with a final result such as CREATE_COMPLETE. If the stack does complete successfully, re-run the provision.yml playbook for it to finish all the additional required steps.

If the stack shows a CREATE_FAILED, make sure to run the following command to see what caused the errors:

$ openstack stack failures list openshift-cluster

Registering with Subscription Manager the OKD Instances

With the nodes successfully provisioned, the next step is to ensure all the nodes are successfully registered via subscription-manager to install all the required packages for a successful OKD installation. For simplicity, a repos.yml file has been created and provided.

$ cat ~/repos.yml
---
- name: Enable the proper repositories for OpenShift installation
  hosts: OSEv3
  become: yes
  tasks:
  - name: Register with activationkey and consume subscriptions matching Red Hat Cloud Suite or Red Hat OpenShift Container Platform
    redhat_subscription:
      state: present
      activationkey: <key-name>
      org_id: <orig_id>
      pool: '^(Red Hat Cloud Suite|Red Hat OpenShift Container Platform)$'

  - name: Disable all current repositories
    rhsm_repository:
      name: '*'
      state: disabled

  - name: Enable Repositories
    rhsm_repository:
      name: "{{ item }}"
      state: enabled
    with_items:
      - rhel-7-server-rpms
      - rhel-7-server-extras-rpms
      - rhel-7-server-ansible-2.4-rpms
      - rhel-7-server-ose-3.10-rpms

Refer to the Set Up Repositories to confirm the proper repositories and versions to enable. The above file is just a sample.

With the repos.yml, run the ansible-playbook command:

$ ansible-playbook repos.yml

The above example uses Ansible’s redhat_subscription and rhsm_repository modules for all registration, disabling and enabling of repositories. This specific example takes advantage of using a Red Hat activation key. If you don’t have an activation key, ensure to visit the Ansible redhat_subscription module to modify using a username and password instead as shown in the examples: https://docs.ansible.com/ansible/2.6/modules/redhat_subscription_module.html

At times, the redhat_subscription module may fail on certain nodes. If this issue occurs, please manually register that OKD instance using subscription-manager.

Installing OKD by Using an Ansible Playbook

With the OpenStack instances provisioned, the focus shifts to the installation OKD. The installation and configuration is done via a series of Ansible playbooks and roles provided by the OpenShift RPM packages. Review the OSEv3.yml file that was previous configured to ensure all the options have been properly set.

Prior to running the installer playbook, ensure all the {rhocp} prerequisites are met via:

$ ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/prerequisites.yml

Run the installer playbook to install Red Hat OpenShift Container Platform:

$ ansible-playbook /usr/share/ansible/openshift-ansible/playbooks/openstack/openshift-cluster/install.yml

Applying Configuration Changes to Existing OKD Environment

Start or restart OKD services on all master and node hosts to apply your configuration changes, see Restarting OKD services:

# master-restart api
# master-restart controllers
# systemctl restart atomic-openshift-node

Switching from not using a cloud provider to using a cloud provider produces an error message. Adding the cloud provider tries to delete the node because the node switches from using the hostname as the externalID (which would have been the case when no cloud provider was being used) to using the cloud provider’s instance-id (which is what the cloud provider specifies). To resolve this issue:

  1. Log in to the CLI as a cluster administrator.

  2. Check and back up existing node labels:

    $ oc describe node <node_name> | grep -Poz '(?s)Labels.*\n.*(?=Taints)'
  3. Delete the nodes:

    $ oc delete node <node_name>
  4. On each node host, restart the OKD service.

    # systemctl restart origin-node
  5. Add back any labels on each node that you previously had.

Configuring OpenStack Variables on an existing OpenShift Environment

To set the required OpenStack variables, modify the /etc/cloud.conf file with the following contents on all of your OKD hosts, both masters and nodes:

[Global]
auth-url = <OS_AUTH_URL>
username = <OS_USERNAME>
password = <password>
domain-id = <OS_USER_DOMAIN_ID>
tenant-id = <OS_TENANT_ID>
region = <OS_REGION_NAME>

[LoadBalancer]
subnet-id = <UUID of the load balancer subnet>

Consult your OpenStack administrators for values of the OS_ variables, which are commonly used in OpenStack configuration.

Configuring Zone Labels for Dynamically Created OpenStack PVs

Administrators can configure zone labels for dynamically created OpenStack PVs. This option is useful if the OpenStack Cinder zone name does not match the compute zone names, for example, if there is only one Cinder zone and many compute zones. Administrators can create Cinder volumes dynamically and then check the labels.

To view the zone labels for the PVs:

# oc get pv --show-labels
NAME                                       CAPACITY   ACCESS MODES   RECLAIM POLICY   STATUS    CLAIM                 STORAGECLASS   REASON    AGE       LABELS
pvc-1faa6f93-64ac-11e8-930c-fa163e3c373c   1Gi        RWO            Delete           Bound     openshift-node/pvc1   standard                 12s       failure-domain.beta.kubernetes.io/zone=nova

The default setting is enabled. Using the oc get pv --show-labels command returns the failure-domain.beta.kubernetes.io/zone=nova label.

To disable the zone label, update the cloud.conf file by adding:

[BlockStorage]
ignore-volume-az = yes

The PVs created after restarting the master services will not have the zone label.