Tag: persistent storage

Total 4 Posts
kubernetes, persistent storage

Kubernetes Persistent Volumes with Deployment and StatefulSet

I get a lot of questions about Kubernetes and persistence. Of course, persistence is important for stateful apps. We often say that for stateful apps you need to use StatefulSet and for stateless apps Deployment. This doesn't mean that you couldn't use deployment to define stateful apps with persistent volumes. For example, the official MySQL Helm chart is using deployment. So, it can be done, but users get confused about this. What is the deal? When should you use deployment ...

kubernetes, ceph, persistent storage

Using Existing Ceph Cluster for Kubernetes Persistent Storage

I wrote about Rook storage a few weeks ago, but maybe you already have Ceph cluster running in your datacenter. Or you prefer to use Ceph on separate nodes and without Kubernetes. Also, currently Rook is alpha software and not ready for production use. I would assume that this large Ceph cluster if you have one, is also used for other services outside Kubernetes. Whatever is the case it is simple to connect Ceph and Kubernetes together to provision persistent ...

kubernetes, persistent storage, resize

Easy Way to Resize Kuberntes Persistent Volumes

The previous post about Rook got great attention from the community. But, I also got a lot of questions about persistence on Kubernetes in general. Among many questions, there were a few about resizing persistent volume claims or PVCs. If you are using on-premises storage solutions like Ceph (Rook) this is not the big issue. The part of the reason is that when you create a volume in Ceph, let's say a 100GB, this space is not actually allocated. But, ...

kubernetes, rook, ceph, persistent storage

Rook: Cloud Native On-Premises Persistent Storage for Kubernetes on Kubernetes

Software defined storage is not something new. One of the most popular is Ceph. I started with Ceph five years ago because I was looking into unified storage for OpenStack. There are many other solutions, but I like the Ceph because it is all in one solution for the block, object and file storage, and it is opensource. Inktank the company behind Ceph is later acquired by RedHat, but that made things even better. If you already have Ceph cluster ...