To get an idea of what is going on, unplug the devices, open a terminal and run
sudo udevadm monitor
Then plug the device and watch the output
Sample of what to expect when attaching a storage device
$ sudo udevadm monitor
[sudo] password for fh:
monitor will print the received events for:
UDEV - the event which udev sends out after rule processing
KERNEL - the kernel uevent
KERNEL[3487.475562] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1 (usb)
KERNEL[3487.475712] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0 (usb)
KERNEL[3487.475820] add /devices/virtual/workqueue/scsi_tmf_20 (workqueue)
KERNEL[3487.475929] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20 (scsi)
KERNEL[3487.476077] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/scsi_host/host20 (scsi_host)
KERNEL[3487.476188] bind /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0 (usb)
KERNEL[3487.476291] bind /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1 (usb)
UDEV [3487.482193] add /devices/virtual/workqueue/scsi_tmf_20 (workqueue)
UDEV [3487.487072] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1 (usb)
UDEV [3487.489910] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0 (usb)
UDEV [3487.491422] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20 (scsi)
UDEV [3487.492961] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/scsi_host/host20 (scsi_host)
UDEV [3487.494403] bind /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0 (usb)
UDEV [3487.498910] bind /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1 (usb)
KERNEL[3488.481693] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0 (scsi)
KERNEL[3488.481785] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0 (scsi)
KERNEL[3488.481912] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/scsi_device/20:0:0:0 (scsi_device)
KERNEL[3488.482018] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/scsi_disk/20:0:0:0 (scsi_disk)
KERNEL[3488.482152] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/bsg/20:0:0:0 (bsg)
UDEV [3488.483946] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0 (scsi)
UDEV [3488.485743] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0 (scsi)
UDEV [3488.487826] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/scsi_device/20:0:0:0 (scsi_device)
UDEV [3488.488518] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/scsi_disk/20:0:0:0 (scsi_disk)
UDEV [3488.489110] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/bsg/20:0:0:0 (bsg)
KERNEL[3488.499165] add /devices/virtual/bdi/8:128 (bdi)
UDEV [3488.501576] add /devices/virtual/bdi/8:128 (bdi)
KERNEL[3488.516201] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/block/sdi (block)
KERNEL[3488.516316] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/block/sdi/sdi1 (block)
KERNEL[3488.516383] bind /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0 (scsi)
UDEV [3488.537727] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/block/sdi (block)
UDEV [3488.560572] add /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/block/sdi/sdi1 (block)
UDEV [3488.562277] bind /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0 (scsi)
KERNEL[3488.594675] change /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/block/sdi/sdi1 (block)
UDEV [3488.614790] change /devices/pci0000:20/0000:20:08.1/0000:23:00.3/usb2/2-1/2-1:1.0/host20/target20:0:0/20:0:0:0/block/sdi/sdi1 (block)