USB_Mass_Storage

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USB

1 Basic Setup

Basic Setup

Kernel Setup

Linux Kernel Configuration:

Device Drivers  --->
    SCSI device support  --->
         -*- SCSI device support
        <*> SCSI disk support
        If you have an USB CD-ROM:
        <*> SCSI CDROM support
    [*] USB support --->
        <*>   Support for Host-side USB
         [*]     USB device filesystem
        <*>     EHCI HCD (USB 2.0) support
        <*>     OHCI HCD support
        <*>     UHCI HCD (most Intel and VIA) support
        <*>   USB Mass Storage support

Alternatively choose some parts as modules. They will be loaded by udev, if needed.

Note: If your USB disk is shown as /dev/ub/a, then you're using the Low Performance USB Block Driver. You will find that your transfer speed is crippled by this driver, because it is designed to meet the lowest common denominator of features for seriously lightweight (or cheap) devices. Disable it and use the usb-storage module instead.

Check Setup

After you plug in a USB storage device run dmesg and see if the USB device was detected:

usb 2-2: new high speed USB device using ehci_hcd and address 5
usb 2-2: configuration #1 chosen from 1 choice
scsi4 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 5
usb-storage: waiting for device to settle before scanning
usb-storage: device scan complete
scsi 4:0:0:0: Direct-Access     USBDisk  RunDisk          1.00 PQ: 0 ANSI: 2
sd 4:0:0:0: [sdb] 8020000 512-byte hardware sectors (4106 MB)
sd 4:0:0:0: [sdb] Write Protect is off
sd 4:0:0:0: [sdb] Mode Sense: 0b 00 00 08
sd 4:0:0:0: [sdb] Assuming drive cache: write through
sd 4:0:0:0: [sdb] 8020000 512-byte hardware sectors (4106 MB)
sd 4:0:0:0: [sdb] Write Protect is off
sd 4:0:0:0: [sdb] Mode Sense: 0b 00 00 08
sd 4:0:0:0: [sdb] Assuming drive cache: write through
sdb: sdb1
sd 4:0:0:0: [sdb] Attached SCSI removable disk
sd 4:0:0:0: Attached scsi generic sg1 type 0

If you get any errors or anything missing, check that the hc drivers and the usb_storage drivers are loaded.