[Warty] /dev/ttyUSB0 changing to /dev/ttyUSB1 !!

[James Wilkinson]

Santanu Chatterjee wrote:
> Hello all,
> 
> I am running Warty (fresh install). I am using a serial modem on a
> presario-2203AL laptop through a usb-to-serial converter, which is
> detected as /dev/ttyUSB0. However, after sometime, while on the net,
> if the modem gets disconnected somehow, then more often than not,
> I cannot use the modem via the same wvdial.conf file since the modem
> still gets detected, but as /dev/ttyUSB1 not ttyUSB0!!  To fix this, I have to
> pull out the usb cord and plug it back to get it detected as ttyUSB0.
> 
> Why this funny behavior?? Any help will be very my appreciated.

Sounds like udev oddities. What you want udev to do is to create a
symlink that will always point at the modem.

I'm at a slight disadvantage here: I don't have the right sort of
hardware to test. But you might find
http://www.reactivated.net/udevrules.php helps, especially
http://www.reactivated.net/udevrules.php#example-printer .

Once you've come up with a suitable name, put it in a new file called
(say) /etc/udev/rules.d/modem.rules .

Then you use the symlink in wvdial, and rely on udev to make sure it
points to the right place.

Hope this helps,

James.

-- 
E-mail address: james | Whenever [Richard I] returned to England he always
@westexe.demon.co.uk  | set out again immediately for the Mediterranean and
                      | was therefore known as Richard Gare de Lyon.
                      |     -- '1066 and All That'