Re: guide to setting up netatalk on Ubuntu, with Apple II netboot

[Hugh Hood <hughhood@earthlink.net>]

Steve,

Those are good points on Netatalk and DDP. And, I suspect that you are
correct about OpenDarwin having the source code for the OS X AppleTalk
stuff.

Here's where things get interesting/confusing. A pre-10.6 OS X Mac _does_
already have an AppleTalk implementation by default, including NBP and
(apparently) DDP. 

For example, I hooked a IIGS up to one of my Mac's and enabled AppleTalk on
both. What follows is the result of the commands "atlookup" and "appletalk
-s":


======START Actual Terminal Session on OS X 10.4.11 =========

Hugh Hood's PowerMac G3:~ hughhood$ atlookup
Found 3 entries in zone *
ffaa.ac.80      Hugh Hood's Power Mac G3:Darwin
ff00.52.80      Silentwriter 95:LaserWriter
ff00.14.81      guest:Apple IIgs
Hugh Hood's PowerMac G3:~ hughhood$

Hugh Hood's PowerMac G3:~ hughhood$ appletalk -s

        AppleTalk interface.............. en0
        Network Number .................. 65450 (0xffaa)
        Node ID ......................... 172 (0xac)
        Current Zone .................... *
        Bridge net ...................... 0 (0x0)
        Bridge number ................... 0 (0x0)

    DDP statistics:

        Packets Transmitted ............. 20
        Bytes Transmitted ............... 828
        Best Router Cache used (pkts) ... 0
        Packets Received ................ 41
        Bytes Received .................. 1761
        Packets for unregistered socket . 0
        Packets for out of range socket . 0
        Length errors ................... 0
        Checksum errors ................. 0
        Packets dropped (no buffers) .... 0
Hugh Hood's PowerMac G3:~ hughhood$

======END Actual Terminal Session on OS X 10.4.11 =========

So, I'm still wondering what it would take for Netatalk to find and use the
default built-in OS X AppleTalk implementation.

Ideally, it would only be a matter of a few Netatalk source code changes.
Or, it could be a major headache that no one would want to take on. I'm not
familiar enough with Netatalk to know exactly how it interacts with the
Linux AppleTalk implementation to speculate.

Any guesses? Anyone?



Hugh Hood



in article gvydnZpKMKB0Lg3RnZ2dnUVZ_hidnZ2d@giganews.com, Steven Hirsch at
snhirsch@gmail.com wrote on 9/15/10 6:54 AM:

> On 09/14/2010 08:33 AM, Ivan X wrote:
>> On 9/14/10 7:49 AM, in article
>> F46dnQdKUKPe_BLRnZ2dnUVZ_i2dnZ2d@giganews.com, "Steven Hirsch"
>> <snhirsch@gmail.com>  wrote:
>> 
>>> On 09/14/2010 12:49 AM, Hugh Hood wrote:
>>> 
>>>> BTW, since you've got a Mac running a pre-10.6 OS (i.e.-AppleTalk still
>>>> present in the kernel, but not available for use by the Mac's native
>>>> AppleFileServer / AFP over TCP/IP only) maybe you could try something at
>>>> which I failed:
>>>> 
>>>> I cheated and used MacPorts to build and install Netatalk, but since that
>>>> patched/configured source refused to allow compiling 'atalkd', I was dead
>>>> in
>>>> the water as far as serving files to an Apple II. I never took it further
>>>> than that, unfortunately.
>>> 
>>> Likely due to lack of kernel-level support for ddp (appletalk transport
>>> layer).  You may well have better luck on an earlier version of OS X.
>> 
>> What Steven said. I too had that idea. While it should theoretically be
>> possible, I tried it some time ago, and netatalk couldn't make use of
>> whatever AppleTalk facilities Mac OS X had. It would probably require
>> modifications to netatalk which are beyond my ability; without really
>> knowing, I'm guessing Linux makes its AppleTalk protocol available in a
>> particular way and that's what netatalk is looking for.
> 
> Well, yes.  The 'particular way' is by supporting Apple's DDP (datagram
> delivery protocol) as a feature of the kernel-level network stack.  Like most
> everything, this is a compile-time option for Linux (which, as you've seen, is
> not activated in your NAS).  Fortunately, since Linux source is available you
> can roll your own.
> 
> Mac OS X is built on top of "Darwin", which I believe is a Mach micro-kernel
> with BSD-ish API (someone correct me if I have this wrong).  Parts of Darwin
> are open source. I suppose if you are adventurous it might be possible to
> build a new Darwin foundation or loadable driver to provide DDP, but a more
> likely approach would involve doing a netatalk-like application with its own
> DDP in user space.  Most modern operating systems have a mechanism for
> applications to plug in as a "tap" at the packet level - not sure what Mac OS
> calls this.
> 
> Either way, it's bound to be a lot of work and a powerful, err, "learning
> experience" :-).
> 
> Steve