Troubleshooting

First, be sure to check if the necessary modules required to run all devices have been correctly loaded.

My mouse doesn't work.

Are hid and mousedev modules loaded? If not, run the commands:

[root@localhost /]# modprobe hid; modprobe mousedev

In text mode, run the commands:

[root@localhost /]# gpm -k ; gpm -t ps2 -m /dev/usb/usbmouse0

For the graphical mode, go the mouse configuration section in your graphical environment (GNOME, KDE, etc.).

My printer doesn't work

Is the printer module loaded? If not, run the command:

[root@localhost /]# modprobe printer

If it still doesn't work, refer to the Printing HOWTO.

What if I don't have a power adapter for the USB hub?

You should only connect low power consumption devices or those that have their own adapter, such as keyboard, mouse, and printer.

My webcam doesn't work

Is the ov511 module loaded? If not, run the command:

[root@localhost /]# modprobe ov511

Is the webcam still not working? Since the webcam requires a lot of power, it should be directly connected to one of the two USB ports on your computer, or to a USB hub powered by an adapter.

What is the maximum length of an USB cable?

The maximum length of fan USB cable is 3 meters, or 9.84 feet.

What can be done so that I do not have to load the modules again every time I restart the computer?

For the keyboard: edit the /etc/rc.d/rc.local file and add the following lines to the end of the file:

modprobe usb-xhci;
modprobe hid;
modprobe keybdev

For the mouse: edit the same file referred to in the problem above, and add the following lines to the end of the file:

modprobe usb-xhci;
modprob hid;
modprobe mousedev

For the printer continue to do the same, and add the following to the end of the /etc/rc.d/rc.local file:

modprobe usb-xhci;
modprobe hid;
modprobe printer

And lastly, for the webcam, add the following lines to the end of the same file you have been editing:

modprobe usb-xhci;
modprobe hid;
modprobe ov511

For more information about USB, visit USB.org.