Re: "pon" fails and gives "ttyS overrun" in syslog

From: Clifford Kite (kite_at_see.signature.id)
Date: 07/06/04

  • Next message: Adrian Holovaty: "Re: Networking doesn't work after remote install" 
    Date: Tue, 6 Jul 2004 11:54:24 -0500

    In comp.os.linux.networking Al Hayes <ashayes@gto.net> wrote:
    > I'm a Debian user and I did an "apt-get upgrade" which upgrades
    > all the Debian packages. However, now, when I execute "pon", my modem
    > won't connect. The modem seems to be making the same connection
    > sounds as before the upgrade; also, the modem is working in Window98.

    > I have syslog records from before/after the upgrade. After upgrade,
    > I notice this message:

    > kernel: ttyS: 1 input overrun(s)
                  ^^^^
    This is the device file that the kernel uses to generate this message,
    see line 504 of the file drivers/char/n_tty.c (at least in a kernel.org
    2.6.4 source). The 1 refers to the number of "input overrun(s)".

    I'd expect it to see ttyS2 since pppd was configured to use ttyS2,
    the serial connection seemed successful, and it appeared that
    ppp0 was attached to ttyS2. Whatever provides the kernel with the
    device file name used in that line seems to have the wrong name.
    I'm not much of a C programmer and trying to follow the code to find
    where the ttyS came from and why it's not ttyS2 is really beyond me.
    But the overrun error is apparently real, although I haven't a clue
    as to what is being overrun.

    The hangup occurs 25 seconds after ppp0 is attached to ttyS2, suggesting
    to me that pppd may have timed out sending LCP Configure-Requests at the
    beginning of the PPP link negotiations, although it's a little shy of
    the 30 seconds that one usually sees when that happens. Adding the pppd
    debug option and looking at the appropriate log file could show whether
    that's what's happening. The log file varies according to distribution
    and I don't use Debian.

    If this is a winmodem, or relative thereof, I'd suspect the kernel
    changed and now the "modem" module is not functioning correctly when
    it starts to send data through the device file.

    ...

    > ==== start of unsuccessful syslog after the upgrade ====

    > Jul 3 20:28:38 box kernel: CSLIP: code copyright 1989 Regents of the
    > University of California
    > Jul 3 20:28:38 box kernel: PPP generic driver version 2.4.2
    > Jul 3 20:28:38 box pppd[1177]: pppd 2.4.2 started by knoppix, uid
    > 1000

    "Started by knoppix?"

    -- Clifford Kite Email: "echo xvgr_yvahk-ccc@ri1.arg|rot13"
    PPP-Q&A links, downloads: http://ckite.no-ip.net/

  • Next message: Adrian Holovaty: "Re: Networking doesn't work after remote install"

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