Introduction 1-5 
Hitachi Universal Storage Platform V/VM Configuration Guide for SGI
®
 IRIX
® 
Host Attachment 
Device Type  Description 
FX Devices (3390-
3A/B/C, OPEN-x-FXoto) 
Using USP V’s Cross-OS File Exchange (FX) feature, you can share data 
across mainframe, UNIX, and PC server platforms using special 
multiplatform volumes. The VLL feature can be applied to FX devices for 
maximum flexibility in volume size. For more information about FX, see the 
Hitachi Cross-OS File Exchange User’s Guide (MK-96RD647), or contact your 
Hitachi Data Systems account team. 
FX devices are not SCSI disk devices, and must be installed and accessed as 
raw devices. UNIX/PC server hosts must use FX to access the FX devices as 
raw devices (no file system, no mount operation). 
The 3390-3B devices are write-protected from UNIX/PC server access. The 
USP V rejects all UNIX/PC server write operations (including fibre-channel 
adapters) for 3390-3B devices. 
Multiplatform devices are not write-protected for UNIX/PC server access. Do 
not execute any write operation by the fibre-channel adapters on these 
devices. Do not create a partition or file system on these devices. This will 
overwrite any data on the FX device and prevent the FX software from 
accessing the device.