Creating a SAN using JMR SHARE
As discussed earlier, a high-availability cluster is valuable for those who rely heavily on continuous access to assets and need assurance assets will never be lost due to a variety of possible disruptions.
Until recently, building a highly available and high-performance Fibre Channel storage area network was quite expensive. The JMR SHARE solution powered by euroNAS provides what were “high cost” features in a lower cost SAN that is also easy to deploy, bringing Enterprise-class SAN functionality to small and medium business operations.
Some benefits of a Fibre Channel SAN are proven reliability, high bandwidth and guaranteed order in delivery of data packets. Users have enjoyed such benefits for years, but often in systems still having a single point of failure, being the primary file server. Drawing on the technology described earlier in the networked HA Cluster, business continuity provided by a SAN cluster is now available for very reasonable cost.
While Ethernet is the most popular network protocol and is low-cost and fairly easy to set-up, it is not designed for transferring block data in a networked storage environment. Ethernet’s way of handling data collisions, when more than one computer tries to transmit data simultaneously, can reduce the network’s efficiency due to retransmissions.
Fibre Channel with its asynchronous design helps assure that even under very heavy load conditions, collisions are handled efficiently to maintain the highest possible throughput.
What Makes It Better?
iSCSI was developed as a cost-effective alternative to Fibre Channel; it is built on an underlying TCP/IP protocol and is normally implemented as a software initiator that incurs substantial processing overhead. By contrast, Fibre Channel commands have been directly implemented into HBAs (Host Bust Adapters), making it more efficient and less CPU consuming. It can be more suitable for data transfers.
One big advantage of Fibre Channel is constant data throughput. While Fibre Channel consistently performs at very close to its line speed, e.g., 8Gb/s or 16Gb/s, collision management on Ethernet makes it difficult to achieve such consistent performance.
The JMR SHARE SAN Cluster is a native Fibre Channel product, designed to provide critical shared data on SAN workloads. When using the SAN Cluster, your network applications will continue to work: No matter if a server fails completely, clients will still have access their data. Using only “backup,” it takes considerable time to recover and manual intervention is usually required to get server and data back on line.
With the SAN Cluster, should a fault occur, it is detected through intelligent features (SSM, or Smart SAN Mirror) and the software automatically moves storage requests to the other server mirrored in the cluster, the same as in HA Cluster discussed earlier. All the benefits of HA Cluster are available in the SHARE SAN Cluster, just using Fibre Channel as the protocol and transport. Using the SAN Cluster will provide:
• Highest redundancy for mission critical applications
• Highest I/O performance thanks to Fibre Channel technology
• Advanced data integrity protection against data corruption
• Multipath I/O technology for even higher redundancy
• Synchronous data mirroring using native Fibre Channel protocol
• Automatic failover
• Failback with fast synchro-nization
• FC port management: Allocate FC targets to single or multiple ports
VMware vSphere® Storage APIs
SAN Cluster supports VMware VSphere Storage APIs – Array Integration (VAAI). SAN Cluster communicates with VMWare ESXI and enables it to offload storage operations to
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