When planning the configuration of external storage systems for use with Lenovo Storage V7000clustered systems, review these details.
See the following website for the latest support information:
http://support.lenovo.com/us/en/products/servers/lenovo-storage
All Lenovo Storage V7000 nodes in a system must be able to connect to the same set of storage system ports on each device. A system that contains any two nodes that cannot connect to the same set of storage-system ports is considered degraded. In this situation, a system error is logged that requires a repair action. This rule can have important effects on a storage system such as an IBM® DS4000® series controller, which has exclusion rules that determine to which host bus adapter (HBA) worldwide node names (WWNNs) a storage partition can be mapped.
A storage-system logical unit (LU) must not be shared between the Lenovo Storage V7000 and a host.
You can configure certain storage systems to safely share resources between the Lenovo Storage V7000 system and direct-attached hosts. This type of configuration is described as a split storage system. In all cases, it is critical that you configure the storage system and SAN so that the Lenovo Storage V7000 system cannot access logical units (LUs) that a host or another Lenovo Storage V7000 system can also access. This split storage system configuration can be arranged by storage system logical unit number (LUN) mapping and masking. If the split storage system configuration is not guaranteed, data corruption can occur.
Besides a configuration where a storage system is split between a Lenovo Storage V7000 system and a host, the Lenovo Storage V7000 system also supports configurations where a storage system is split between two Lenovo Storage V7000 systems. In all cases, it is critical that you configure the storage system and SAN so that the Lenovo Storage V7000 system cannot access LUs that a host or another Lenovo Storage V7000 system can also access. You can use storage system LUN mapping and masking to arrange for this configuration. If this configuration is not guaranteed, data corruption can occur.
When a storage system is detected on the SAN, the Lenovo Storage V7000 attempts to recognize it using its Inquiry data. If the device is not supported, the Lenovo Storage V7000 configures the device as a generic device. A generic device might not function correctly when it is addressed by a Lenovo Storage V7000 system, especially under failure scenarios. However, the Lenovo Storage V7000 system does not regard accessing a generic device as an error condition and does not log an error.