[luau] Linux Console

[MonMotha]

Brian Chee wrote:
> 1.    don't use hyperterminal....it's had LOTS of wierd side effects.  We've
> especially had problems with it on embedded devices.  Use teraterm
> instead...still free, but MUCH better terminal emulation. Hyperterminal
> actually prevented a linux based router from booting until I removed the
> serial cable.  It's also given me MUCH gas pain with QNX and VXworks based
> RTOS machines. (real time operating systems for stuff like video appliances,
> access points, switches, etc)

I agree.  Hyperterminal can give you lots of headaches, but it usually 
works for me.

> 
> 2.    You're just needing a standard cross over cable...you can purchase one
> from just about any computer store or make one.  They're also called "lap
> link serial cables" and that's what I tend to use all over my lab.  They
> have both a DB-25 and  DB-9 at both ends so that I don't have to worry about
> what kind of connector I have.
> 
> 3.    The technical term is a DTE to DTE cable.....
> 
> 4.    Typically these are the pinouts normally used in cross over cables
> (DB9 female to female):
> 
> PC side:        Server Side:
> pin 2                pin 3
> pin 3                pin 2
> pin 4                pin 6
> pin 5                pin 5
> pin 6                pin 4
> pin 7                pin 8
> pin 8                pin 7
> 
> Wacky Willy's on Kawaihao street has DB-9 to RJ-45 shells for under a buck
> each....best price in town.  Just make sure you get the gender correct and
> use a multimeter to check which pin goes where.
> 
> 5.    Lastly, most motherboards do not have the capability of using a serial
> port as a true console device.  (ala Sun sparcs) and thusly you don't get a
> console until the linux/bsd/etc is up and running.  Some of the Intel
> motherboards do have a true serial console...the cool part about that is
> that you can actually connect a terminal/console server (like the Lantronix
> SSH terminal servers) to the console.  I've created a airgapped network
> (separate from the world) just for console devices (Networld+Interop calls
> it "Access Ether") so that even if I'm getting dos'ed I can get into the
> console and deal with it. I've done some of my servers and almost all of my
> switches.  That way I can get into a serial console without having to walk
> all over my building....even better when you have to deal with a campus.
> 

This is a problem, but normally an inconsequential one.  Most of the 
time, as long as the system can boot to a bootloader properly, the 
person won't need to access the BIOS config utility and such.  LILO has 
an option to actually display all it's prompts on the serial console 
too.  Most of the time, if you need to get into the BIOS config, enough 
stuff is wrong with the system you might as well hook a keyboard and 
video card up to it :)

--MonMotha