Posts tagged: longhorn

All posts with the tag "longhorn"

2 posts latest post 2025-08-15
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Aug 2025 | 1 posts
💭 Performance Difference between RWX and RWO volumes · longhorn/... github.com
Performance Difference between RWX and RWO volumes · longhorn longhorn · Discussion #6964 Hey all, because of some internal testing I made a couple of experiments on our Cluster related to performance of RWX and RWO volumes. Because this might be of interest to some people I thought I s... GitHub · github.com [1] Interesting longhorn storage performance test, author does highlight right away that this is a simulation and not a REAL test. I did not fully understand the storage semantics before reading through this. - RWO - Always presents a filesystem ext4 or xfs - RWX/ROX - Always presents a network share nfs to the pod. This is an important distinction for applications that use sqlite or a tool on top of sqlite such as diskcache. With sqlite it is not recomended to run over nfs due to missing required file locking mechanisms. Longhorn storage still provides a lot of benefits to these applications as the storage is automatically replicated, if the node that your application is running on goes offline a new pod will start on an existing node. If you have planned downtime, you can cordon and drain a node. Since the data is available in another location you will be able to s...

Changing k8s Storage Class - Migration Job

I’m setting up longhorn in my homelab [1], and I ran into an issue where I initially setup some pvcs under longhorn, and later realized that to get longhorn to snapshot and backup I needed to hand edit volumes after the fact or change storage class. I’m all in on gitops so option 1 was not an option. So changing storageclass it is. Now the issue is that you CANNOT mutate storageclass on a provisioned pvc, it is an immutable attribute. Migration Job # [2] This migration job will create a new pvc with the new storageclass and move the data from the old pvc to the new pvc. Existing Pods This migration job will not work if you have a pod using the old pvc. You will need to shutdown the pod and delete it. # old pvc with longhorn storageclass apiVersion: v1 kind: PersistentVolumeClaim metadata: name: site-pvc-longhorn namespace: waylonwalker-com spec: storageClassName: longhorn-backup accessModes: - ReadWriteOnce resources: requests: storage: 5Gi # new pvc with longhorn-ba...