Tag Archives: openshift

OpenShift

How to specify your vSphere virtual machine resources when deploying Red Hat OpenShift

When deploying Red Hat OpenShift to VMware vSphere platform, there are two methods:

  • User Provisioned Infrastructure (UPI)
  • Installer Provisioned Infrastructure (IPI)

There are several great blogs covering both options and deployment methods.

In this blog, we are going to use the IPI method but customize the settings of our Virtual Machines that are deployed setting CPU and Memory that is different from the default settings.

Getting Started
Setting up your Jump host Machine

I’ll be using an Ubuntu Machine as my jumphost for the deployment.

Download the OpenShift-Install tool and OC command line tool. (I’ve used version 4.6.4 in my install)

Extract the files and copy to your /usr/bin/local directory

tar -zxvf openshift-client-linux.tar.gz
tar -zxvf openshift-install-linux.tar.gz

Have an available SSH key from your jump box, so that you can connect to your CoreOS VMs one they are deployed for troubleshooting purposes.

You need to download the vCenter trusted root certificates from your instance and import them to your Jump Host.

Curl -O https://{vCenter_FQDN}/certs/download.zip

Then the following to import (ubuntu uses the .crt files, hence importing the win folder);

unzip download.zip
cp certs/win/* /usr/local/share/ca-certificates
update-ca-certificates

You will need an account to connect to vCenter with the correct permissions for the OpenShift-Install to deploy the cluster. If you do not want to use an existing account and permissions, you can use this PowerCLI script to create the roles with the correct privileges based on the Red Hat documentation.

If you are installing into VMware Cloud on AWS, like myself, you will also need to allow connectivity from your segments as follows:

  • Compute gateway
    • OCP Cluster network to the internet
    • OCP Cluster network to your SDDC Management Network
  • Management gateway
    • OCP Cluster network to ESXi – HTTPs traffic

DNS Records – You will need the two following records to be available on your OCP Cluster network in the same IP address space that your nodes will be deployed to.

  • {clusterID}.{domain_name}
    • example: ocp46.veducate.local
  • *.apps.{clusterID}.{domain_name}
    • example: *.apps.ocp46.veducate.local

If your DNS is a Windows server, you can use this script here. Continue reading How to specify your vSphere virtual machine resources when deploying Red Hat OpenShift

OpenShift

Red Hat OpenShift on VMware vSphere – How to Scale and Edit your cluster deployments

Working with Red Hat OpenShift on vSphere, I’m really starting to understand the main infrastructure components and how everything fits together.

Next up was understanding how to control the cluster size after initial deployment. So, with Red Hat OpenShift, there are some basic concepts we need to understand first, before we jump into the technical how-to’s below in this blog.

In this blog I will cover the following;

- Understanding the concepts behind controlling Machines in OpenShift
- Editing your MachineSet to control your Virtual Machine Resources
- Editing your MachineSet to scale your cluster manually
- Deleting a node
- Configuring ClusterAutoscaler to automatically scale your environment

Machine API

The Machine API is a combination of primary resources that are based on the upstream Cluster API project and custom OpenShift Container Platform resources.

The Machine API performs all node host provisioning management actions as a post cluster installation method, providing you dynamic provisioning on top of your VMware vSphere platform (and other public/private cloud platforms).

The two primary resources are:

Machines
An object that describes the host for a Node. A machine has a providerSpec, which describes the types of compute nodes that are offered for different cloud platforms. For example, a machine type for a worker node on Amazon Web Services (AWS) might define a specific machine type and required metadata.
MachineSets
Groups of machines. MachineSets are to machines as ReplicaSets are to Pods. If you need more machines or must scale them down, you change the replicas field on the MachineSet to meet your compute need.

These custom resources add capabilities to your OpenShift cluster:

MachineAutoscaler
This resource automatically scales machines in a cloud. You can set the minimum and maximum scaling boundaries for nodes in a specified MachineSet, and the MachineAutoscaler maintains that range of nodes. The MachineAutoscaler object takes effect after a ClusterAutoscaler object exists. Both ClusterAutoscaler and MachineAutoscaler resources are made available by the ClusterAutoscalerOperator.
ClusterAutoscaler
This resource is based on the upstream ClusterAutoscaler project. In the OpenShift Container Platform implementation, this is integrated with the Machine API by extending the MachineSet API. You can set cluster-wide scaling limits for resources such as cores, nodes, memory, GPU, etc. You can configure priorities so that the cluster prioritizes pods so that new nodes are not brought online for less important pods. You can also set the ScalingPolicy, so that for example, you can scale up nodes but not scale down the node count.

MachineHealthCheck

This resource detects when a machine is unhealthy, deletes it, and, on supported platforms, creates a new machine. You can read more here about this technology preview feature in OCP 4.6.

Editing your MachineSet to control your Virtual Machine Resources

To view the current MachineSet objects available run; Continue reading Red Hat OpenShift on VMware vSphere – How to Scale and Edit your cluster deployments

OpenShift

Using the vSphere CSI Driver with OpenShift 4.x and VSAN File Services

You may have seen my blog post “How to Install and configure vSphere CSI Driver on OpenShift 4.x“.

Here I updated the vSphere CSI driver to work the additional security constraints that are baked into OpenShift 4.x.

Since then, once of the things that has been on my list to test is file volumes backed by vSAN File shares. This feature is available in vSphere 7.0.

Well I’m glad to report it does in fact work, by using my CSI driver (see above blog or my github), you can simply deploy consume VSAN File services, as per the documentation here. 

I’ve updated my examples in my github repository to get this working.

OK just tell me what to do…

First and foremost, you need to add additional configuration to the csi conf file (csi-vsphere-for-ocp.conf).

If you do not, the defaults will be assumed which is full read-write access from any IP to the file shares created.

[Global]

# run the following on your OCP cluster to get the ID 
# oc get clusterversion -o jsonpath='{.items[].spec.clusterID}{"\n"}'
cluster-id = c6d41ba1-3b67-4ae4-ab1e-3cd2e730e1f2

[NetPermissions "A"]
ips = "*"
permissions = "READ_WRITE"
rootsquash = false

[VirtualCenter "10.198.17.253"]
insecure-flag = "true"
user = "administrator@vsphere.local"
password = "Admin!23"
port = "443"
datacenters = "vSAN-DC"
targetvSANFileShareDatastoreURLs = "ds:///vmfs/volumes/vsan:52c229eaf3afcda6-7c4116754aded2de/"

Next, create a storage class which is configured to consume VSAN File services.

kind: StorageClass
apiVersion: storage.k8s.io/v1
metadata:
name: file-services-sc
annotations:
storageclass.kubernetes.io/is-default-class: "false"
provisioner: csi.vsphere.vmware.com
parameters:
storagepolicyname: "vSAN Default Storage Policy" # Optional Parameter
csi.storage.k8s.io/fstype: "nfs4" # Optional Parameter

Then create a PVC to prove it works. Continue reading Using the vSphere CSI Driver with OpenShift 4.x and VSAN File Services

OpenShift

How to Install and configure vSphere CSI Driver on OpenShift 4.x

Introduction

In this post I am going to install the vSphere CSI Driver version 2.0 with OpenShift 4.x, in my demo environment I’m connecting to a VMware Cloud on AWS SDDC and vCenter, however the steps are the same for an on-prem deployment.

I have updated the available configuration files available from Red Hat for installing the CSI Driver in OpenShift, to make them compatible with the latest CSI Driver. You can find these in my GitHub repo;

- Pre-Reqs
- - vCenter Server Role
- - Download the deployment files
- - Create the vSphere CSI secret in OpenShift
- - Create Roles, ServiceAccount and ClusterRoleBinding for vSphere CSI Driver
- Installation
- - Install vSphere CSI driver
- - Verify Deployment
- Create a persistent volume claim
- Using Labels
- Troubleshooting

In your environment, cluster VMs will need “disk.enableUUID” and VM hardware version 15 or higher.

Pre-Reqs
vCenter Server Role

In my environment I will use the default administrator account, however in production environments I recommend you follow a strict RBAC procedure and configure the necessary roles and use a dedicated account for the CSI driver to connect to your vCenter.

To make life easier I have created a PowerCLI script to create the necessary roles in vCenter based on the vSphere CSI documentation;

Download the deployment files

Run the following;

git clone https://github.com/saintdle/vSphere-CSI-Driver-2.0-OpenShift-4.git

Create the vSphere CSI Secret in OpenShift

Edit the file “csi-vsphere-for-OCP.conf” with your vCenter infrastructure details;

[Global]
 
# run the following on your OCP cluster to get the ID
# oc get clusterversion -o jsonpath='{.items[].spec.clusterID}{"\n"}'
cluster-id = "OCP_CLUSTER_ID"

[VirtualCenter "VC_FQDN"]
insecure-flag = "true"
user = "USER"
password = "PASSWORD"
port = "443"
datacenters = "VC_DATACENTER"

Create the secret;

oc create secret generic vsphere-config-secret --from-file=csi-vsphere-for-OCP.conf --namespace=kube-system

oc get secret vsphere-config-secret --namespace=kube-system

This configuration is for block volumes, it is also supported to configure access to VSAN File volumes, and you can see an example of the configuration here;

Remove your “csi-vsphere-for-OCP.conf” once the secret is created, as it contains your password in clear text for vCenter.

Create Roles, ServiceAccount and ClusterRoleBinding for vSphere CSI Driver

Continue reading How to Install and configure vSphere CSI Driver on OpenShift 4.x

OpenShift

How to deploy OpenShift 4.3 on VMware vSphere with Static IP addresses using Terraform

Install OpenShift 4.x on vSphere 6.x/7.x

The following procedure is intended to create VM’s from an OVA template booting with static IP’s when the DHCP server can not reserve the IP addresses.

The Problem

OCP requires that all DNS configurations be in place. VMware requires that the DHCP assign the correct IPs to the VM. Since many real installations require the coordination with different teams in an organization, many times we don’t have control of DNS, DHCP or Load balancer configurations.

The CoreOS documentation explain how to create configurations using ignition files. I created a python script to put the network configuration using the ignition files created by the openshift-install program.

Reference Architecture

For this guide, we are going to deploy 3 master nodes (control-plane) and 2 worker nodes (compute This guide uses RHEL CoreOS 4.3 as the virtual machine image, deploying Red Hat OCP 4.3, as per the support of N-1 from Red Hat.

We will use a centralised Linux server (Ubuntu) that will perform the following functions;

  • Load Balancer – HAProxy
  • Web Server – Apache2
  • Terraform automation host – version 0.11.14
    • The deployment will be semi-automated using Terraform, so that we can easily build configuration files used by the CoreOS VM’s that have Static IP settings.
    • Using a later version of Terraform will cause failures.
  • Client Tools for OpenShift deployment
    • OC
    • Kubectl
    • Openshift-install

DNS will be provided by a Windows Server.

The installation will use a Bootstrap server to bring the cluster online, which will be removed at the end of the build process.

Deployment Steps

In this guide we will deploy our environment in the following order;

  • Configure DNS
  • Import Red Hat Core OS image into vCenter
  • Deploy Ubuntu Host
    • Configure Apache
    • Configure HAProxy
    • Install Client-Tools
    • Install Terraform
  • Build OpenShift Cluster configuration
  • Configuring the Terraform deployment
  • Running the Terraform deployment
DNS

Openshift uses a “clusterName.BaseDomain” format.

For example; I want to call my Openshift cluster Demo. And my DNS Domain is Simon.local, then my full format used by Openshift is “demo.simon.local”

Below is a table plan of the IP addresses you will use to build the environment.

The last three addresses are cluster level resources that are available on each control-plane node, accessible via the load balancer.

To configure the DNS records in Windows, you can use the Script and CSV file here

In the below screenshot, the script has created the “demo” domain folder and entered my records. It is important that you have PTR records setup for everything apart from the “etcd-X” records.

Import Red Hat CoreOS Image into vCenter

Continue reading How to deploy OpenShift 4.3 on VMware vSphere with Static IP addresses using Terraform