Cirrus Data has developed a technology called Transparent Datapath Intercept (TDI, US Patents No. 8,255,538 and 8,417,818 — click on the Patents tab to learn more). TDI eliminates all of the pain points of deploying an in-band storage gateway appliance on a live FC SAN.

TDI technology is the basis of all of Cirrus Data’s solutions and offers enormous flexibility for data centers to perform migration or add caching without concern of potential downtime. Migrating data or adding a cache solution shouldn’t take IT organizations months to complete. Cirrus Data can provide the easy-to-implement solutions that address your SAN migration or SAN caching needs.

Using TDI as a foundation, CDS created the Data Migration Server (DMS) and Data Caching Server (DCS) to provide truly plug-and-play, risk-free, no-downtime data migration and data caching services to existing SANs. There are several available Transparent Datapath Intercept insertion methods that can be used depending on the SAN environment requirements and restrictions in place for the client hosts and LUNs to be migrated. None of the insertion methods require downtime for the client hosts or storage, nor do they disrupt the production environment.

1. U.S. Patent No. 8,255,538: Systems and methods for intercepting data relating to storage volume access

This Cirrus Data Solutions patent is a powerful, comprehensive protection for CDS’s Transparent Data Interception (TDI) technology. TDI is a novel and ingenious invention which involves a unique architecture and design and which uses standard storage HBA ports to create a transparent data path as a virtual cable. The technology provides the capability to insert an appliance in-band between the host and the storage without causing downtime and without requiring any changes to the host, the switch, and the storage. The appliance automatically discovers the WWPN of each storage target port and host initiator port once connected, thus allowing it to be totally transparent. The result is a true plug-and-play technology that provides the basis for a number of solutions including data migration, data caching, and data replication.

2. U.S. Patent No. 8,417,818: Systems and methods for intercepting data relating to storage volume access

The second Cirrus Data Solutions patent extends the coverage of the TDI invention to additional storage protocols, such as iSCSI, SATA, Infiniband, and others. While specific technical details of TDI may vary from protocol to protocol, the same transparent datapath insertion results can be achieved using clever manipulation of these existing storage connectivity protocols to seamlessly insert this “virtual cable” into the data path. In the end, the TDI technology is once again transparently and stealthily embedded into production environments, and the same desirable storage services can be added to existing storage configurations using many other storage protocols.

3. U.S. Patent No. 9,077,752: Systems, apparatus, and methods for identifying stored data that may be accessed by a host entity and providing data management services

This Cirrus Data Solutions patent extends the coverage of the TDI invention to host-side intercept, with all the protocols covered in the previous patents. In addition, this patent also covers the configuration where vSAN, or Virtual Fabric capable switches can be used for increasing the fan-in/fan-out ratio. This increases the efficiency of the Nexus to allow one-to-many intercept, meaning a single nexus can be used to intercept multiple links. With the host-side intercept, and the one-to-many configuration, a single pair of CDS appliances with few Nexus can be used to intercept a large environment with many storage links. Frequently the number of storage paths provided by these links are not present for performance reasons, but rather appear due to simplified redundancy configuration. By consolidating the paths transparently, the system can be intercepted by reducing the over redundant paths without performance degradation and without introducing risk.

4. U.S. Patent No. 9,229,647: Systems, Methods, and Apparatus for Spoofing a Port of a Host Entity to Identify Data that is Stored in a Storage System and May be Accessed by the Port of the Host Entity

The fourth Cirrus Data Solutions patent extends the protection of the host side intercept technique, which allows selected interception of storage links and limits the scope of exposure. The enhanced technique provides greater flexibility and scope in supported configurations and topologies in enterprise storage environments. The added flexibility and control significantly increases the range and variety of applications using the intercept mechanism. In addition to data migration and centralized data caching, the technology can also be extended to data protection with backup, archiving, as well as malware detection, and possible data intrusion, thus making it possible to enable a complete line of advanced network storage functions.

5. U.S. Patent No. 9,298,390: Systems and methods for copying data maintained in a dynamic storage volume and verifying the copied data

U.S. Patent No. 9,298,390 is the 5th patent granted to Cirrus Data Solutions Inc. This invention is a mechanism implemented to dynamically track data images migrated for integrity verification. The Cirrus Data migration appliance performs data migration on a live production environment where the data continues to change during the migration process. The Cirrus Data migration operation is asynchronous, and is performed in a multi-pass manner. Time slots are customized for weekdays, weekends, or holidays, each with specified aggressiveness. This flexible migration system allows data to be migrated efficiently, yet with minimal impact to production traffic. The dynamic data image tracking mechanism is created to enable verification of the data under this kind of dynamic operating environment. With this invention, the migrated data can be verified whenever a consistent intermediate image is achieved, independent of the capricious nature of the source data as well as the potentially elaborate migration schedule, therefore ensuring the fidelity of the migrated data.

6. U.S. Patent No. 9,495,113: Systems, devices, apparatus, and methods for identifying stored data by a device located in a path between virtual Fibre Channel switches and performing a data management service.

U.S. Patent No. 9,495,113 is the 6th patent granted to Cirrus Data Solutions Inc. It covers the logical insertion technique for both host side and storage side configurations. With the logical insertion technique, storage links can be transparently inserted using switch commands either manually, or via the DMS insertion wizard. The current wizard supports most popular switch models, including Brocade and Cisco. Using the technique described in this patent, DMS appliances are inserted into active data paths without touching any physical cables in the storage environment. DMS appliances are simply connected into the production switches and logically inserted into data paths in a completely transparent manner, with zero disruption to the data I/O. Selected data volumes can then be migrated with minimal or no impact to production. This insertion technique also provides the most flexibility and scalability for planning and execution of mass data migration. In large environments, hosts can be selectively migrated, leaving the rest of the storage environment untouched an unaffected by migration.

7. U.S. Patent No. 9,542,120: Systems and methods for processing instructions while repairing and providing access to a copied volume of data.

U.S. Patent No. 9,542,120 is the 7th patent granted to Cirrus Data Solutions Inc. It covers the test view device method. During data migration, new destination LUNs are kept in a crash consistent state, which allows the application servers to test mount and review the data on the LUNs before the final cut-over occurs. During this time, the source and destination LUNs data differences are tracked, so each newly changed block in the source LUNs can be resynchronized to the destination LUNs as long as the LUNs are not yet cut-over. However mounting the intermediate images may change the data in the destination LUNs, which will disrupt the data relationship. The invention covered by this patent is a method to protect the destination data image while allowing unlimited access to the LUNs, ensuring the data relationship is maintained while the intermediate data images are reviewed and tested.

Image of U.S. Patents Issued for Cirrus Data Solutions

CDS Patents

Additional Patents Pending

Same or additional patents are filed, or prepared to be filed in other regions, including the European Union, China, Japan, and/or other jurisdictions applicable for intellectual property protection.

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