Re: [K12OSN] Some beginner questions..

[Eric Harrison <eharrison mail mesd k12 or us>]

On Sat, 29 Nov 2003, James Mayfield wrote:

>Hello,
>
>I have just started experimenting with a little test lab using k12ltsp. 
>Absolutely cool stuff!  I just have a few questions.

Mineral? Heh. I grew up in Red Bluff.

I will probably be heading back to Red Bluff for Christmas if you
want a hand ;-)

>We are going to be using recycled and donated computers for workstations
>for the most part.  We will be getting nic cards with bootroms and all
>to make things easy, but I am wondering about sound.  

Everyone wonders about remote sound. It is hard to do, but we have
been spending a lot of time trying to make it as easy as possible.

>They will quite
>likely all have different sound card.  I am not quite clear on how that
>part works.  With my little test server here, I can manage to login
>workstations via pxe on my laptop, and using a boot floppy an another
>computer, but sound doesnt work.  Seems it is expecting to find the card
>that the server has.  In the lab, we would certainly think about
>unifying them sound card wise if it makes things easier.
>
>Thanks.  I can't wait to get this up and running. 

The first rule of thumb is that ISA sound cards are aweful. Avoid
them whenever possible. Your success rate will be much higher with
PCI sound cards. (same rule applies to any ISA vs PCI card)

More often than not, PCI cards "just work".

If you cannot avoid ISA sound cards, you'll have to come up with 
a strategy to mitigate the pain. You might want to keep a spare
workstation around that you can stick in the sound card. If you
are lucky, when you boot with the new sound card in it it will be
detected and auto-configured for you. If so, skip the next step
which is: run "redhat-config-soundcard" and fiddle with the settings
until it makes sound.  Once you have the card working ok, you will
find the settings in /etc/modules.conf. This file will contain
something like:

   alias sound-slot-0 sb
   options sb 0x220,5,1      (made up, I don't have an old card to test)

Take these settings and add a new section to your /opt/ltsp/i386/etc/lts.conf
with the MAC address for the terminal that the sound card will go into.
For example:

	[00:40:05:37:14:32]
        SMODULE_01  = sb io=0x220 irq=5 dma=1

where:

   "00:40:05:37:14:32" is the MAC address of the network card in the
   terminal that will have this sound card

   "sb" is the sound module to load (Sound Blaster ISA is common)

   "io=0x220 irq=5 dma=1" are the IO, IRQ, and DMA settings for the card


Beyond just getting the sound card initialized, there are a couple of
different ways of redirecting sound from the server to the terminal.

The current default is to use "esd", but we are slowly switching over
to using "nasd". If you are running a current, fully patched, version
of K12LTSP on your server, you can test "nasd" by adding this line
to the "[Default]" section of /opt/ltsp/i386/etc/lts.conf

   SOUND_DAEMON = "nasd"


Other than that, expect to be asking a lot of questions here on
the list.

-Eric