Following on from my previous post on this topic, a number of people reached out to ask about how to add read-write-many (RWX) volumes to a Pod in VKS. Again, for dynamic volumes, this is quite simple to do. But what about some static volumes which were initially created by the Volume Service. This is a summary of what I posted in my previous blog in relation to RWX volumes. “Since RWX volumes are back by vSAN File Shares in VCF 9.0, you will need to have vSAN File Service enabled and configured. You will also have to tell the…
I have been spending some time looking at the new Volume Service in VMware Cloud Foundation (VCF) 9.0. Through VCF Automation, is is possible for tenants of VCF to provision their own volumes. These volumes can be consumed by the VM Service, something that has been a part of the Supervisor Services for many years. However, it is also possible for workloads running in VKS, the vSphere Kubernetes Service, to consume the static volumes provisioned via the Volume Service. In this post, I will show you the steps to create a static volume via the Volume Service, and then create…
I’m writing this post because of a misconception I had regarding how read-only volumes were configured in Kubernetes. I thought this was controlled by the accessModes parameter in the PersistentVolumeClaim manifest file. This is not the case. It is controlled from the Pod, which to me seems a bit strange. Why would this not be controlled from the PVC manifest? One of our engineers pointed me to a few Kubernetes discussions on the behaviour of accessModes and readOnly here and here. It would seem that I am not the only one confused by this behaviour. In this post, I deploy…
After a very eventful VMworld, we received lots of questions about CNS, the Cloud Native Storage feature that was released with vSphere 6.7U3. Whilst most of the demonstrations and blog articles around CNS focused on vSAN, what may have been missed is that this feature also works with both VMFS and NFS datastores. For that reason, I decided to create some examples of how CNS can also bubble up information in vSphere about Kubernetes Persistent Volumes (PVs) created on both VMFS and NFS datastores. Let’s begin by creating some simple policies to tag my VMFS datastore and my NFS datastore.…
I have been doing quite a bit of work on First Class Disks (FCD), also known as Improved Virtual Disks (IVD) over the past number of months. One tool that has been extremely useful in improving my understanding of FCDs has been safekeeping, a tool developed by Max Daneri of VMware and which is now available to download on GitHub. If you did not know, FCDs are used extensively in VMware’s new Cloud Native Storage (CNS) offering that is currently available with vSphere/vSAN 6.7U3. Now, whilst the primary aim of this tool is to help backup vendors become familiar with…
In my lab, I run a number of different flavors of Kubernetes. Some of them I deploy via kubeadm. Others I have provisioned by VMware PKS. Some of these can access the outside world, while others are secured. Sometimes it is difficult to figure out the relationship between various K8s objects – which services, endpoints, PVs and PVCs are used by different Pods or StatefulSets. In the past I have used the K8s dashboard, but more often than not, I have to start kube proxy and then run some sort of tunnel (via PuTTY or similar) in order to be…
In my most recent 101 post on ReadWriteMany volumes, I shared an example whereby we created an NFS server in a Pod which automatically exported a File Share. We then mounted the File Share to multiple NFS client Pods deployed in the same namespace. We saw how multiple Pods were able to write to the same ReadWriteMany volume, which was the purpose of the exercise. I received a few questions on the back on that post relating to the use of Services. In particular, could an external NFS client, even one outside of the K8s cluster, access a volume from…