Introduction
SUSE® Storage is a lightweight, reliable and easy-to-use distributed block storage system for Kubernetes.
With SUSE Storage, you can:
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Use SUSE Storage volumes as persistent storage for the distributed stateful applications in your Kubernetes cluster
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Partition your block storage into SUSE Storage volumes so that you can use Kubernetes volumes with or without a cloud provider
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Replicate block storage across multiple nodes and data centers to increase availability
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Store backup data in external storage such as NFS or AWS S3
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Create cross-cluster disaster recovery volumes so that data from a primary Kubernetes cluster can be quickly recovered from backup in a second Kubernetes cluster
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Schedule recurring snapshots of a volume, and schedule recurring backups to NFS or S3-compatible secondary storage
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Restore volumes from backup
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Upgrade SUSE Storage without disrupting persistent volumes
SUSE Storage comes with a standalone UI, and can be installed using Helm, kubectl, or the Rancher app catalog.
Simplifying Distributed Block Storage with Microservices
Because modern cloud environments require tens of thousands to millions of distributed block storage volumes, some storage controllers have become highly complex distributed systems. By contrast, SUSE Storage can simplify the storage system by partitioning a large block storage controller into a number of smaller storage controllers, as long as those volumes can still be built from a common pool of disks. By using one storage controller per volume, SUSE Storage turns each volume into a microservice. The controller is called the Longhorn Engine.
The Longhorn Manager component orchestrates the Longhorn Engines, so they work together coherently.
Use Persistent Storage in Kubernetes without Relying on a Cloud Provider
Pods can reference storage directly, but this is not recommended because it doesn’t allow the Pod or container to be portable. Instead, the workloads' storage requirements should be defined in Kubernetes Persistent Volumes (PVs) and Persistent Volume Claims (PVCs). With SUSE Storage, you can specify the size of the volume, the number of synchronous replicas and other volume specific configurations you want across the hosts that supply the storage resource for the volume. Then your Kubernetes resources can use the PVC and corresponding PV for each SUSE Storage volume, or use a SUSE Storage storage class to automatically create a PV for a workload.
Replicas are thin-provisioned on the underlying disks or network storage.
Schedule Multiple Replicas across Multiple Compute or Storage Hosts
To increase availability, SUSE Storage creates replicas of each volume. Replicas contain a chain of snapshots of the volume, with each snapshot storing the change from a previous snapshot. Each replica of a volume also runs in a container, so a volume with three replicas results in four containers.
The number of replicas for each volume is configurable in SUSE Storage, as well as the nodes where replicas will be scheduled. SUSE Storage monitors the health of each replica and performs repairs, rebuilding the replica when necessary.