You can also connect a second computer to the one you are booting off of with 
a null modem cable and use serial console.  Hit any key other than <enter> 
when the boot  loader message shows up and at the resulting prompt type:
consdev <serial port>

On i386, is used "pccom0" for the first serial port.  Your other computer 
needs a serial terminal program set to 9600 baud, 8 data bits, no parity, 1 
stop bit.

Make sure you set up the terminal to have a nice scrollback buffer so you can 
cut and paste if you need to email for help.

>===== Original Message From Alexander Flott <aflott-netbsd@gmx.de> =====
>> hi guys,
>>
>> how is it possible to get the boot output when booting from install
>> floppies? the output of the boot kernel goes just too fast and i need to
>> see what it is reporting...
>>
>> i looked around the mfs that it creates, but no /var/log/messages can be
>> found. dmesg is also not present. what can i do to get the information?
>
>There should be /kern/msgbuf which contains install-kernel output.
>
>HTH
>-Alex

George Morgan