A Lenovo Storage V seriesclustered system has several features that can be used to deploy a high-availability storage system with no single point of failure.
Volume mirroring provides protection against a storage system failure by mirroring data across storage systems. For example, for disaster recovery, the Metro Mirror and Global Mirror features can be used to mirror data between systems at different physical locations. In addition, in the HyperSwap system topology, a volume can be active on two I/O groups at different sites; if one site becomes unavailable, the volume can immediately be accessed by the other site.
Each I/O group within a system consists of a pair of node canisters. If a node fails within an I/O group, the other node canister in the I/O group assumes the I/O responsibilities of the failed node canister.
For example, when using Fibre Channel SAN-attached hosts, attach the node canisters to at least two SAN fabrics, and attach each host system to both fabrics.
Each Lenovo Storage V series node has four Fibre Channel ports, which can be used to attach the node to multiple SAN fabrics. For high availability, attach the node in a system to at least two fabrics. For high availability, attach the node in a system to at least two fabrics. For high availability, attach the node canister in a system to at least two fabrics. Lenovo Storage V seriessoftware incorporates multipathing software to communicate with Lenovo Storage V seriesnodes. This software is also used for I/O operations among Lenovo Storage V seriesnode and storage systems. If a SAN fabric fault disrupts communication or I/O operations, the multipathing software recovers and tries the operation again through an alternative communication path. For high availability, configure your Fibre Channel host systems to use multipathing software. If a SAN fabric fault or node failure occurs, I/O operations among Fibre Channel host systems and Lenovo Storage V seriesnode are tried again. Subsystem device driver (SDD) multipathing software is available from IBM at no additional charge for use with Lenovo Storage V series. For more information about subsystem device driver (SDD), go to the Support for IBM Systems website and enter the product name in the Product Finder field:
iSCSI-attached hosts connect to Lenovo Storage V series through node Ethernet ports. If a node fails, Lenovo Storage V series fails over the IP addresses to the partner node in the I/O group to maintain access to the volumes.