Date: Wed, 19 Jun 2002 16:30:08 -0700 From: "Aaron Burke" <aburke@nullplusone.com> To: "FreeBSD-Questions" <freebsd-questions@freebsd.org>, <pjklist@ekahuna.com> Subject: RE: Serial console issues Message-ID: <NGBBLCIHCLNJAIGIFFHJGEKBCFAA.aburke@nullplusone.com> In-Reply-To: <20020619162802043.AAA668@empty1.ekahuna.com@pc02.ekahuna.com>
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<snip> > > > > > You should be able to use "dmesg | grep sio" to determine > what kind > > > > > of hardware you are running. > > > > > > > > I'm fairly certain it isn't the hardware, at least in my case. > > > > I've used several different machines that were at least > > > relatively recent > > > > hardware (at least past the point where they wouldn't have > had a 16550 > > > > uart) and the serial console exhibited the same behavior each time. > > > > > > > > > In my case I'm not able to get the serial console working at all. > > > All I get on my display is some periodic commas and D characters. > > > I have it set for Xon/Xoff flow control. I have had similar problems in the past. The reasons for the garbage have generally been speed related for me. I have just had to do things like make sure the Dumb Term and Serial port both communicate at the same speed. It appears that you have at least browsed over the communications settings. Also, the fact that you are getting info on the terminal at all does mean that the BSD box is sending data to it. > > I believe that unless your box does not have a keyboard attached the > > box does not turn on COM1 unless you have specified that you want a > > login on /dev/cuaa1. You will want to check /etc/ttys for this value. > > I dont remember if its turned on by default, but I always turn it on > > myself. Also, unless you make changes to the boot loader, the system > > will default to the primary graphics adapter. But your suggestion of > > -Dh may fix the problem. I used to have that configured, but not any > > more, so your guess is better than mine right now. > > > Hmm. Well I got the impression the login getty was optional, I > figured at least I'd get console boot messages without enabling a > login in /etc/ttys. It seems that using the login getty is not the results your looking for. > > According to the handbook section on serial consoles, all you are > supposed to need is to make sure the kernel config enables console > mode on a serial port (seems to be the default now on COM1) and > create a /boot.config file using one or more of the following > switches: > > -D (sends initial console output to both video and serial) > > -h (toggles console output - ie if normally to video, makes it go to > serial) > > -P (this is the switch that is supposed to only redirect console > output to serial if there is no keyboard attached) > > > >From what I gather, recompiling the boot blocks is only required if I > want to do something like change the default console COM port, or the > default speed. (but as you know others mentioned they couldn't get > the speed to change anyway) > > I just updated the "BMC" code (Baseboard Management Controller) on > the board which has some control over serial management stuff, but it > didn't help. Everything else is the latest. > > I even tried 2 different kinds of "null modem" cables. (So did you > know that both HP and Intel console cables for their Ethernet > switches are not only different from, and incompatible with each > other, but also different than a standard null modem cable? Reminds > me of the old adage: "The nice thing about standards is, there are so > many to choose from..." :-) > > > > > Current FBSD versions appear to enable console operations by default > > > on sio0, (with the "flags 0x10" argument in the kernal config file) > > > so in theory all I should have to do is connect a null-modem cable, > > > run a comm program at 9600,N,8,1 - create a boot.config file with a > > > "-D" or "-h" or "-Dh" in it (or specify it to the boot loader at boot > > > time) and get something. I don't get any output. You are right about the "flags 0x10". But by default (if my memory is correct) the com port will only be used if the box is turned on without a keyboard, or booted with one of the boot switches. "-Dh" Has worked for me in the past. > > > I'm going to try it on another box and see if it's hardware related. > > > > Ok but also check that /etc/ttys is configured the same way as the > > terminal that your gonna attach. > > > I'll go ahead and do that, although I would have thought it wouldn't > have any bearing on whether I should have been seeing boot messages > or not - given the fact that among other things, they all come before > a login prompt would appear. Actually, dont update /etc/ttys. It sounds like you are requesting the console on /dev/cuaa0 as well. Changing this file will give you a seperate terminal here. I dont this that this is what you want. <snip> To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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