Very Computer

I am using an Inside Out networks edgeport/4 connected to a pc running
Redhat 7.1 (kernel 2.4.5).  I had mgetty and and /etc/inittab files
configured correctly and all worked well, except after dialing in once,
when you disconnect no more calls would be accepted until the machine was
rebooted.  A patch was then made available to fix this problem, which it
sort of did.  You could call the modem and then call again and again with
no problem.  THe problem is that when trying to log in to the server
after connecting, I enter my username and after about 5 seconds it
disconnects.  mgetty.config, /etc/inittab entry, and mgetty.log files
below.  Your help is greatly appreciated.

mgetty.config
port ttyUSB0
        data-only

inittab
USB0:2345:respawn:/sbin/mgetty -x 3 ttyUSB0

mgetty.log

06/29 07:20:34 SB0  mgetty: experimental test release 1.1.25-Feb01
06/29 07:20:34 SB0  check for lockfiles
06/29 07:20:34 SB0  locking the line
06/29 07:20:34 SB0  lowering DTR to reset Modem
06/29 07:20:34 SB0  TIOCMBIC failed: Invalid argument
06/29 07:20:34 SB0  send: \dATQ0V1H0[0d]
06/29 07:20:35 SB0  waiting for ``OK'' ** found **
06/29 07:20:35 SB0  send: ATS0=0Q0&D3&C1[0d]
06/29 07:20:35 SB0  waiting for ``OK'' ** found **
06/29 07:20:35 SB0  waiting...
06/29 07:26:32 SB0  wfr: waiting for ``RING''
06/29 07:26:32 SB0  send: ATA[0d]
06/29 07:26:32 SB0  waiting for ``CONNECT'' ** found **
06/29 07:26:46 SB0  send:
06/29 07:26:46 SB0  waiting for ``_'' ** found **
06/29 07:26:48 ##### data dev=ttyUSB0, pid=959, caller='none', conn='31200
        V42bis', name='', cmd='/bin/login', user='wood'

--
06/29 07:26:48 SB0  mgetty: experimental test release 1.1.25-Feb01
06/29 07:26:48 SB0  check for lockfiles
06/29 07:26:48 SB0  locking the line
06/29 07:26:49 SB0  WARNING: DCD line still
06/29 07:26:49 SB0  WARNING: DCD line still active, check modem settings
        (AT&Dx)06/29 07:26:49 SB0  lowering DTR to reset Modem
06/29 07:26:49 SB0  TIOCMBIC failed: Invalid argument
06/29 07:26:49 SB0  send: \dATQ0V1H0[0d]
06/29 07:26:49 SB0  waiting for ``OK'' ** found **
06/29 07:26:51 SB0  send: ATS0=0Q0&D3&C1[0d]
06/29 07:26:51 SB0  waiting for ``OK'' ** found **
06/29 07:26:51 SB0  waiting...

Thanks again,
--Aaron

That's a USB device which is not fully compatibel, as it doesn't
really have the needed control lines that mgetty uses to check for
the status of the modem. The driver solves _most_ of the resulting
problems, but not all. See below:

[...]

Quote:>06/29 07:20:34 SB0  lowering DTR to reset Modem
>06/29 07:20:34 SB0  TIOCMBIC failed: Invalid argument

Typically, with a serial modem, this would indicate a
broken cable or an incorrect modem setting.

[...]

Quote:>06/29 07:26:49 SB0  WARNING: DCD line still
>06/29 07:26:49 SB0  WARNING: DCD line still active, check modem settings
>    (AT&Dx)06/29 07:26:49 SB0  lowering DTR to reset Modem

[...]

Same as above. Mgetty notices the DCD line status, tries to
lower the DTR line to reset the modem, which fails as
there IS no DTR line. This is essentially a driver problem.
It would be interesting to see whether connecting a USB-to-
serial converter with a standard serial modem would exhibit
an identical behaviour.

Michael
--

          Lumber Cartel Unit #456 (TINLC) & Official Netscum
    Note: If you want me to send you email, don't munge your address.

The edgeport/4 I mentioned is a usb-to-serial converter.  The Modem is a
serial modem.
--Aaron

[...]

Quote:>The edgeport/4 I mentioned is a usb-to-serial converter.  The Modem is a
>serial modem.

In this case, either the modem is setup incorrectly (with regards
to the DTR/DCD behaviour), the cable is broken, or the converter
(and/or its driver) doesn't fully use support the serial lines
that mgetty trusts upon.

Michael
--

          Lumber Cartel Unit #456 (TINLC) & Official Netscum
    Note: If you want me to send you email, don't munge your address.