Overview

The IBM System Storage DS3950 Express Models 94 and 98 and the EXP395 Express Expansion Unit deliver 8 Gbps FC/1 Gbps iSCSI high-performance and affordable host midrange disk storage solution.

DS3950 Express Models 94 and 98
The DS3950 Express Model 94 (SEO, part number 181494H) and DS3950 Express Model 98 (SEO, part number 181498H) disk systems are packaged in 3U rack mountable enclosure that houses 16 drive bays, redundant dual-active intelligent RAID controllers, and dual power supplies and cooling components. On its initial release, both express models of the DS3950 had an internal storage capacity of up to 16 TB physical storage using 1000 GB SATA DDMs or up to 9.6 TB physical storage using 600 GB Fibre Channel DDMs. In subsequent controller releases, the DS3950 supports 900GB 10K FC-SAS and 3TB SAS disk drives.

EXP395 Express Storage Expansion Unit
The EXP395 Express Expansion Unit (SEO, part number 181492H) is packaged in a 3U rack-mountable enclosure, contains 16 drive bays, dual switched 4 Gbps ESMs, and dual power supplies and cooling components. On its initial release, the EXP395 Expansion Unit had a physical storage capacity of up to 16 TB per enclosure using 1000 GB SATA DDMs, and up to 9.6 TB per enclosure using 600 GB FC DDMs. In subsequent controller releases, the EXP395 supports 900GB 10K FC-SAS and 3TB SAS disk drives.

Expansion Shelf	Maximum # of Enclosures	Drive Type
EXP395 and DS3950 Internal	6 Expansion Enclosures x 16 Drives per Enclosure
EXP810	6 Enclosures x 16 Drives per Enclosure

The DS5020, DS3950, EXP5000, EXP810, EXP520, and EXP395 FC-SAS drives must have the FC-SAS interposer firmware version 2264 or later installed. Some drives with FC-SAS interposer firmware version earlier than 2264 report incorrect inquiry information during Start of Day. This causes the controller firmware to make the drive uncertified (incompatible), which in turn causes the drive to no longer be accessible for I/O. This condition will also cause the associated array to go offline. Since the array is no longer accessible, the controller firmware may not recover the cache for all LUNs under this array. This behavior may result in data not being written. The FC-SAS interposer firmware version 2268 is available in the ESM/HDD firmware package version 1.78 or later.

Contact us if you need more information or integration assistance for your IBM DS3950 Series of products or EXPansion units.