Greg Folkert wrote:
Both of the drives that I tried are passive. The system detects that a new USB device is attached, it just does not configure the device. The following output from dmesg show the drive plugged directly into the cable as being detected (on address 29) and configured. Then I disconnect the device and plug in the hub which is also detected (address 30). I then plugged in the drive to the hub and you can see that it is detected (address 31) just like when it is plugged directly to the cable, but it does not configure the device and no device files are created. Unfortunately, I do not have any other types of USB devices to test and see if the hub causes problems for them as well (in which case I would just toss the hub).On Thu, 2007-04-26 at 21:36 -0700, Marc Shapiro wrote:Does anyone have a clue why /dev/sda and /dev/sda1 are created and the drive will mount if plugged directly to the cable, but /dev/sda and /dev/sda1 are not created if the drive is plugged into the detected and configured hub (yes, I have tried all four ports on the hub)?Is it a powered or passive USB hub? Powered == gets electrical power from a power supply other than the USB port. Passive == get all power from the USB port only. If passive, there might just not be enough power being supplied from the USB port. Also, many many many problems reported to the Kernel USB list are resolved by using a new good quality cable. It is scary at how many issues are indeed resolved this way.
usb 4-4: new high speed USB device using ehci_hcd and address 29 usb 4-4: configuration #1 chosen from 1 choice scsi6 : SCSI emulation for USB Mass Storage devices usb-storage: device found at 29 usb-storage: waiting for device to settle before scanning Vendor: Memorex Model: Flashdrive 303B Rev: PMAP Type: Direct-Access ANSI SCSI revision: 00 SCSI device sda: 62912 512-byte hdwr sectors (32 MB) sda: Write Protect is off sda: Mode Sense: 23 00 00 00 sda: assuming drive cache: write through SCSI device sda: 62912 512-byte hdwr sectors (32 MB) sda: Write Protect is off sda: Mode Sense: 23 00 00 00 sda: assuming drive cache: write through sda: sda1 sd 6:0:0:0: Attached scsi removable disk sda sd 6:0:0:0: Attached scsi generic sg0 type 0 usb-storage: device scan complete usb 4-4: USB disconnect, address 29 usb 4-4: new high speed USB device using ehci_hcd and address 30 usb 4-4: configuration #1 chosen from 1 choice hub 4-4:1.0: USB hub found hub 4-4:1.0: 4 ports detected usb 4-4.1: new high speed USB device using ehci_hcd and address 31 usb 4-4.1: no configuration chosen from 1 choice -- Marc Shapiro mshapiro_42@yahoo.com