RADOS and ViPR

In continuation of the document I wrote about Object store here, I want to bring up two emerging technologies and their role. RADOs is an object store which also allows BlockIO(iSCSI) gateway and NAS gateways. Together with Ceph for Openstack, it eliminates the storage silos that usually form with different protocols. In addition, it can support S3 and Swift APIs. This unified approach also helps with maintainability. Essentially the nature of any object store is to export a server’s local disk space into a single large datastore. Software that maintains this functionality saves data in binary form. As in a cluster computing, the number of nodes participating in this technology is arbitrary and hence the perception of seamlessly scalable storage. This can support billions of objects that are identified by their ID. 

ViPR addresses a different point of unification. It brings the legacy gear typical of a datacenter into a single unified storage. It provides more management convenience that VMWare is known for. Behind its façade, it connects different legacy servers that maintains their protocol centric behavior. By protocols, I mean ftp, http, cifs, nfs, etc. Centralized automated management reduces storage provisioning tasks against each of these protocols. 

How does RADOS work? 

RADOS stands for reliable autonomic distributed object store. It consists of three different layers: 

1. Object Storage Device: An OSD in RADOS is always a folder within an existing filesystem. Together the OSD form the object store. RADOS generates binary objects from the files to be stored and stashes it in the store 

2. Monitoring Servers (MON) These form the interface to the RADOS store and support access to the objects within the store.  

3. Metadata servers (MDS) MDS provides POSIX metadata for objects in the RADOS object store for CEPH clients. 

Ceph is the file-system that accesses the object store in the background. Ceph is closer to the user while RADOS powers it. Without Ceph the data is not accessible to the user. However RADOS is not limited to being the backend of a filesystem. It can work with others. 

ViPR can work with a variety of systems and a variety of services. It’s a one stop management utility for software as a service. While it is widely recognized that each storage platform can handle specific workloads, each comes with its own specific APIs, management and monitoring tools. ViPR eliminates this overhead and provides a common automatic provisioning and management portal. 

ViPR enables automatic storage management for use by VMWare, Openstack and Microsoft clients. It provides access via a unified OPEN REST APIs across a dozen types of virtual storage arrays. Moreover, it’s multivendor support is 11extensible.  

Both ViPR and RADOS seem to provide seamless unlimited storage. While RADOS provides new form of storage, ViPR can transform the existing storage infrastructure into a simple and extensible platform. 
Bool hasNode ( node root, node target) {
If root  == null return false;
If target == null return false;
If root == target  return true;
Return hasNode (root.left, target) || hasNode (root.right, target);

}