Missing serial port after enabling serial console in loader.conf
Jeremy Chadwick
freebsd at jdc.parodius.com
Tue Apr 12 23:08:26 UTC 2011
On Tue, Apr 12, 2011 at 11:13:06PM +0200, Pawel Tyll wrote:
> >> P.S. -- What's "BMC" stand for?
> > Baseband Management Controller. It's the separate NIC (sometimes it's
> > piggy-backed on a NIC) used for remote management of motherboards.
> > Usually includes IPMI support. Depending on the motherboard, it may
> > even include support for keyboard/video/mouse redirection and
> > serial-over-lan and all that other remote management stuff.
>
> Actually, the board in reference has built-in BMC; it's IPMI managed
> and when properly configured it allows user to ssh to its IP and
> access things like SOL, chassis power control and other IPMI things
> without any IPMI clients. As to video redirection, there's addon for
> that, built-in BMC doesn't have anything that fancy. And on point, I
> was having similar problems with these boards some time ago, but it
> seems it has been fixed somewhere between 8.1 and 8.2.
If I remember correctly from following commits, there were changes to
the boot loader pertaining to serial port initialisation. I think I
remember something about certain control bits being set/reset when they
should have been masked out (left alone).
As I understand it, the serial console capabilities on FreeBSD are
tested predominantly with motherboards that have on-board serial ports.
That is to say, systems with classic/legacy DB9 ports on the board
itself and not via IPMI or out-of-band management modules (re: BMC).
So, one should not be too surprised that there may be "oddities" seen
with those.
I imagine that UART enumeration/initialisation might differ on such
modules, so this sort of problem doesn't surprise me much. Marcel
Moolenaar (author of uart(4)) probably has better insights.
--
| Jeremy Chadwick jdc at parodius.com |
| Parodius Networking http://www.parodius.com/ |
| UNIX Systems Administrator Mountain View, CA, USA |
| Making life hard for others since 1977. PGP 4BD6C0CB |
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