USB Mass Storage Devices

All USB storage devices in this Solaris release are now accessed as removable media devices. This change has the following advantages:

• USB storage devices with standard MS-DOS or Windows (FAT) file systems are now supported.

• You can use the user-friendly rmformat command instead of the format command to format and partition all USB storage devices. If the functionality of the format command is needed, use the format -e command.

• You can use the fdisk command if you need to do fdisk-style partitioning.

• Non-root users can now access USB storage devices, since the root-privileged mount command is no longer needed. The device is automatically mounted by vold and is available under the /rmdisk directory. If a new device is connected while the system is down, do a reconfiguration boot with the boot -r command so that vold recognizes the device. Note that vold does not automatically recognize a hot-plugged device. If a new device is connected while the system is up, restart vold. For more information, refer to the vold(1M) and scsa2usb(7D) man pages.

• Disks with FAT file systems can be mounted and accessed. For example:

  mount -F pcfs /dev/dsk/c2t0d0s0:c /mnt

• All USB storage devices are now power managed, except for those that support LOG SENSE pages. Devices with LOG SENSE pages are usually SCSI drives connected through a USB-to-SCSI bridge device. In previous Solaris releases, some USB storage devices were not power managed because they were not seen as removable media.

• Applications might work differently with USB mass storage devices. Keep the following issues in mind when using applications with USB storage devices:

  • Applications might make incorrect assumptions about the size of the media since only smaller devices like diskettes and Zip drives were removable previously.

  • Requests by applications to eject media on devices where this would be inapplicable, such as a hard drive, will succeed and do nothing.

  • If you prefer the behavior in previous Solaris releases where not all USB mass storage were treated as removable media devices, then you can force the old behavior by updating the /kernel/drv/scsa2usb.conf file.

For more information on using USB mass storage devices, see the scsa2usb(7D) man page.

Troubleshooting Tips for USB Mass Storage Devices

Keep the following tips in mind if you have problems adding or removing a USB mass storage device.

• If USB devices are added or removed when the system is down, you must perform a reconfiguration boot.

  ok boot -r

  If you have problems accessing a device that was connected while the system is running, try the following command:

  # devfsadm

• Do not move devices around if the system has been powered down by a suspend operation. For more information, see SPARC: USB Power Management.

• If a device has been hot removed while in use by applications and is no longer available, then stop the applications. Use the prtconf command to see whether the device node has been removed.