Cisco Systems is working on a service that will enable changes to be made to a storage network without affecting the data being sent across it at the same time.
When Sans are busy serving data, reconfiguring storage environments through the data path can slow the network down.
Cisco is to offer an application programming interface for its MDS 9000 switches which, it said, will allow partners' products to engage in out-of-band communications with the San without disrupting data flow.
The Data Tap Service provides a protocol-based interface between the Cisco MDS 9000 San switches and third-party storage appliances, allowing appliances to access servers and storage devices on a San without having to be directly in the path of the data.
It will be demonstrated by Cisco and three partners - Alacritus, for disk-based data protection products, Kashya for business continuity and Topio for data recoverability - at Storage Networking World in Phoenix, Arizona, in early April.
The service will be available as a feature on one of the line cards for the Cisco MDS 9000 and therefore for use on any of the modular chassis.
This approach differs from having storage applications actually run on the fabric, as is the case with Brocade Communications Systems' FAP7420. Alacritus is porting its virtual tape application to that platform.
So there are now two approaches, with the storage switch either hosting the third-party software or providing a side door through which it can access the San.
Chris Mellor writes for IDG