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Ctera has outlined plans for KubeFiler, which will provide persistent storage for Kubernetes clusters in the cloud while acting as if it was local.
KubeFiler uses container storage interface (CSI) drivers to provide access for Windows users and via virtual machines as if it was providing storage from a local NAS device.
“We are increasingly seeing applications run in containers rather than virtual machines or on bare metal servers,” said Aron Brand, technical director at Ctera during the recent virtual edition of the IT Press Tour.
“We have had lots of demand from clients to adapt our products to this new format because access in this way makes provision of storage for containers much easier.”
Containerised applications are at the leading edge of moves towards working cloud-natively, so without need of the likes of NAS storage, but for businesses in the process of such a transformation, there are benefits of continuing to use it.
In part, that is because for now, organisations are focused on containerising existing applications that work with traditional storage. The benefit of these deployments is that containers are easier to use than virtual machines. It is in this context that myriad CSI drivers have been developed that allow Kubernetes to mount storage from traditional arrays in its containers’ workspaces.
“There are lots of benefits to accessing traditional NAS, rather than a modern object storage service,” said Brand. “Starting with the fact that you can maintain secure access to your applications with the proven rules you’ve always used. But storage in the cloud is more interesting than NAS, such as those from Dell EMC (Isilon) or NetApp that don’t allow you to share content between several sites or between remote workers.
“However, the attraction of the Ctera solution is primarily that it caches the most-accessed files locally. To be sure, KubeFiler isn’t a cloud storage service – it accelerates transfers to and from the cloud.”
KubeFiler is built on similar components to those previously developed by Ctera. Chiefly, that is a local client that presents as a NAS server and which holds the cache.
Read more on container storage
- Kubernetes storage 101: Container storage basics. We look at the basics of creating storage and specifying it for applications in container storage using Kubernetes Persistent Volumes and Persistent Volume Claims.
- Container storage 101: What is CSI and how does it work? We look at the container storage interface, which provides an interface to persistent storage in the products of storage array makers, and how it relates to Kubernetes.
This local client can be on a workstation or mobile app, a standalone appliance on the network based on HPE’s hyper-converged Simplivity for branches of more than 20 people, or the smaller HC100 appliance with 1TB of NVMe storage to connect branches with up to 20 users.
Behind that, online access provides the interface between each local instance and the cloud part of the service. Ctera calls this ensemble its Global File System.
That mechanism allows sharing of the same storage between multiple sites – branch offices, teleworkers’ PCs, and so on. The cloud storage itself can be from AWS, Microsoft Azure or IBM Cloud. It can also be from any private cloud that is based on OpenStack Swift.
Ctera makes the point that it is also compatible with object storage in a centralised datacentre. Its software recognises, in addition to S3, the proprietary object storage of Dell EMC (ECS), NetApp (StorageGrid), Hitachi Vantara (HCP) and Scality.
Ctera’s solutions come with multiple tools ranging from anti-virus to decontaminate shared files, to an analytics console that delivers summaries of file access activity.
Other suppliers have come up with similar systems, namely Nasuni and Panzura, and also NetApp with Talon. “These solutions have less cache – which degrades performance – don’t have a mobile client and are less secure,” said Brand.
On the roadmap for KubeFiler is a rearchitecting of the online service so that it also works in containers, but for now it runs from a virtual machine.