Kubernetes Storage on vSphere 101 – NFS revisited

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…

Kubernetes Storage on vSphere 101 – ReadWriteMany NFS

Over the last number of posts, we have spent a lot of time looking at persistent volumes (PVs) instantiated on some vSphere back-end block storage. These PVs were always ReadWriteOnce, meaning they could only be accessed by a single Pod at any one time.  In this post, we will take a look at how to create a ReadWriteMany volume, based on an NFS share, which can be accessed by multiple Pods. To begin, we will use an NFS server image running in a Pod, and show how to mount the exported file share to another Pod, simply to get the…

NFS TCP Connections on vSphere revisited

Some time back, nearly 6 years ago in fact, I wrote about how you might hit the NFS maximum value for the number of connections you can have per IP address when mounting a lot of shares from the same NFS target. You can find the article in question here. The question came up again recently, and I found that a few things have changed since I wrote that post. In this updated post, thanks to some feedback from our NFS engineers, I wanted to revisit this scenario and explain in some further detail what the limits are. First of…