SUMMARY: Attempting to get serial console working after booting with keyb/monitor

From: Jeremy Doran (
Date: Thu Oct 08 1998 - 00:42:12 CDT

My original question:
> Here's the situation as it stands at the moment. I have 3 Sun Ultra 1's
> in our server room, and the intention is to connect them to a Livingston
> Portmaster 2e to act as a console server. The console server is not the
> issue here, as I have already successfully connected one of the ultras
> to it, and verified all this by using the same dumb terminal and serial
> cable on all three machines.
> The problem is with the other two ultras. I believe that they were
> both booted with a keyboard and monitor attached, so the console output
> and device where the 'console login' prompt is, is currently the graphics
> console. Am I right with this assumption?
> Assuming that I am, then booting the machines without a keyboard attached
> would direct the console to the serial ports.
> However, these servers are live production servers, and at the current
> time rebooting them is not an option.
> So, here's the first part of the question; Based on my assumptions above,
> is there any way to change the default console device on a running system
> to be a serial device without having to reboot the system?
> The next part is if my assumption above was wrong. If so, then for
> some reason the serial ports on these two ultras are not working. I've
> already done some checking on this side, and from the PROM level the
> serial settings for the machine that has a working serial port matches
> that of the settings for a machine that does not work. Also, the output
> from 'pmadm -l' on both working and non-working machine seems to indicate
> that both ttya and ttyb are being monitored (though I no almost nothing
> about SAF here) So maybe the serial ports have got into some kinda state
> and need resetting somehow. Or is there something else that I should be
> checking?

Thanks to Casper Dik <casper@holland.Sun.COM> for this, which seemed like it
did the trick. At least, on issuing the following, graphics certainly was
disabled and i/o went elsewhere. Unfortunately, the contract I was on ended
before I got the answer, so was unable to fully test this solution.

} ... But disconnecting the keyboard would have most likely put the
} systems in "prom" mode.
} If the keyboard and consoel are still connected and you can live
} witha few seconds of down time, you can redirect the console
} of teh PROM by doing:
} ttya io
} in PROM mode.
} I think that this will also redirect Solaris console I/O, but I'm not
} 100% sure.
} You'll need to type "go" on the terminal server to get the system
} running again.

Thanks also to those who answered me with suggestions:
Thomas Lester <>
Russ Poffenberger <>
Kevin Sheehan - Uniq <>
O'Neal,Chris <>

I'm only sorry that I'm not able to report on the success or failure of
the suggestions :(

J C Doran

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