Re: tip and serial console

From: Roberto Quiroga (noswen_at_example.net)
Date: 01/27/04

  • Next message: Chris Cox: "Re: *** Time share on Unix?" 
    Date: Tue, 27 Jan 2004 00:24:57 -0300

    dfreybur@yahoo.com (Doug Freyburger) escribió:

    > Roberto Quiroga wrote:
    >>
    >> I use tip to control headless pc, sometimes the session runs for days
    >
    > So don't do that. Logout when you're finished doing your work. Same
    > sort of login cleanliness practice SAs are supposed to teach users, we
    > are supposed to use ourselves to set a good example.

    It is handy for monitoring, I use screen in an xterm and swatch to
    monitor logs in a number of machines, now with ssh via Ethernet but I
    prefer a serial terminal because I can monitor the startup process
    also and I think it is more secure. I log as a normal user and use
    sudo to start the monitoring. I understand and appreciate your
    concerns.

    >> but if the other machine is shutdown, the machine running tip hangs
    >> hard (no keyboard leds, no access from network).
    >> The SO is Openbsd 3.4 i386, the line in /etc/remote is:
    >> com2s:dv=/dev/cua01:br#9600:pa=none:
    >
    > cua01 is a device that uses hardware handshake. It "should" come back
    > once the serial line on the far end comes back online, but if there is
    > a login session there, it is waiting for input to come online. A
    > catch-22 sitution.
    >
    >> the serial ports in dmesg are:
    >> pccom0 at isa0 port 0x3f8/8 irq 4: ns16550a, 16 byte fifo <=serial mouse
    >> pccom1 at isa0 port 0x2f8/8 irq 3: ns16550a, 16 byte fifo <=null modem cable (3 wire)
    >
    > Find a /dev/tty* device that maps to the same hardware and use it.
    > Software handshake rather than hardware handshake, no more catch-22.

    I change the line in /etc/remote to:
    com2s:dv=/dev/tty01:br#9600:pa=none:

    it works, but if the other machine is shutdown the machine running tip
    hangs but now the keyboard leds works, I can not change screens. When
    the other machine comes back there is no change and I must reboot
    (hard) the monitoring machine. 

    -- 
Roberto Quiroga
  • Next message: Chris Cox: "Re: *** Time share on Unix?"

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