Low level debugging of removable devices

This document (7000505) is provided subject to the disclaimer at the end of this document.

Environment

SUSE Linux Enterprise Desktop 10
SUSE Linux Enterprise Server 10

Situation

External hardware devices like e.g. USB hard drives are to be used, but they do not get enabled and/or are not listed by lsusb as either connected or known devices.

Resolution

The detection process with udev, HAL and DBUS (which are the low level services for detecting and activating hardware) can be monitored in detail.

The first command that can be used for this purpose is:

lshal --monitor

The second one is:

dbus-monitor --system

Use these two commands while connecting and disconnecting the non-working devices.

Additionally debugging output for udev can be enabled with the following command:

udevcontrol log_priority=debug

When debugging is finished, the value can be reset to its default err through the following command:

udevcontrol log_priority=err

Additional Information

Example

The following is the output from lshal --monitor when a USB stick gets detected and activated successfully:

Start monitoring devicelist:
-------------------------------------------------
09:38:12.826: usb_device_90c_1000_AA04012700007504 added
09:38:13.056: usb_device_90c_1000_AA04012700007504_if0 added
09:38:13.934: usb_device_90c_1000_AA04012700007504_if0_scsi_host added
09:38:13.935: usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0 added
09:38:13.938: usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0_scsi_generic added
09:38:14.171: storage_serial_USB_Flash_Disk_AA04012700007504_0_0 added
09:38:14.190: volume_uuid_2757_A5DE added
09:38:18.737: usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0_scsi_generic removed
09:38:18.745: volume_uuid_2757_A5DE removed
09:38:18.749: usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0 removed
09:38:18.750: usb_device_90c_1000_AA04012700007504_if0_scsi_host removed
09:38:18.752: storage_serial_USB_Flash_Disk_AA04012700007504_0_0 removed
09:38:18.758: usb_device_90c_1000_AA04012700007504_if0 removed
09:38:18.762: usb_device_90c_1000_AA04012700007504 removed

The output from dbus-monitor --system in the same case looks like this:

signal sender=org.freedesktop.DBus -> dest=:1.6884 path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameAcquired
   string ":1.6884"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0_scsi_host"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0_scsi_generic"
signal sender=org.freedesktop.DBus -> dest=(null destination) path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameOwnerChanged
   string ":1.6885"
   string ""
   string ":1.6885"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/storage_serial_USB_Flash_Disk_AA04012700007504_0_0"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceAdded
   string "/org/freedesktop/Hal/devices/volume_uuid_2757_A5DE"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0_scsi_generic"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/volume_uuid_2757_A5DE"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0_scsi_host_scsi_device_lun0"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0_scsi_host"
signal sender=org.freedesktop.DBus -> dest=(null destination) path=/org/freedesktop/DBus; interface=org.freedesktop.DBus; member=NameOwnerChanged
   string ":1.6885"
   string ":1.6885"
   string ""
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/storage_serial_USB_Flash_Disk_AA04012700007504_0_0"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504_if0"
signal sender=:1.1 -> dest=(null destination) path=/org/freedesktop/Hal/Manager; interface=org.freedesktop.Hal.Manager; member=DeviceRemoved
   string "/org/freedesktop/Hal/devices/usb_device_90c_1000_AA04012700007504"

Disclaimer

This Support Knowledgebase provides a valuable tool for SUSE customers and parties interested in our products and solutions to acquire information, ideas and learn from one another. Materials are provided for informational, personal or non-commercial use within your organization and are presented "AS IS" WITHOUT WARRANTY OF ANY KIND.