Re: network booting

[Jonno Downes <jonnosan@gmail.com>]

On Jan 15, 12:46 am, ol...@web.de (Oliver Schmidt) wrote:
>
> >I don't expect to have to support multiple NICs but it would be nice
> >to have an IP stack with some published  stable entry points in
> >firmware.
>
> Indeed. Given the fact that both on the C64 and the Apple2 the
> currently popular Ethernet solution don't use interrupts but just
> heavy polling the API is conceptually very straight forward. However
> it could be hard to decide on the API level:
>
> - Low level raw ethernet packet I/O
>   - With or without implicit ARP handling
> - Mid level IPv4 packet I/O
>   - With or without implit ICMP handling
> - High level TCP I/O
>   - TCP not supported by IP65 afaik

I would like to see IP+RARP+DHCP+ICMP+UDP (which is what you get with
IP65).

>
> >but I do plan to make a standalone server
> >(probably in ruby so it's OS neutral) that combines serving boot
> >images via TFTP (and also handles DHCP if people don't already have a
> >DHCP server on their network, although most people do have something
> >like  a broadband router) along
>
> Unfortunately things aren't that rosy: Typical DHCP servers,
> especially the ones in broadband routers, don't allow you to specify a
> boot file name to be downloaded via TFTP. So you need your own DHCP
> server to do so, but that server interferes with the almost already
> existing one :-(

I'm working around this by
1) using a specific name for the boot file (BOOTA2.BIN / BOOTC64.PRG)
for Apple 2 and C64 respectively
2) sending the initial TFTP d/l request as a broadcast (although all
the ACKs go back the specific IP address of the server that is sending
the file).

That way any existing DHCP server should work "out of the box", and
the TFTP will succeed as long as there is no other TFTP server on the
LAN (since it would probably send a "no such file" error in response
to the broadcast file d/l request). I think this will handle the most
common case (i.e. people have broadband routers with DHCP, but
typically won't have a TFTP server set up as well, if they do they are
probably know enough to sort things out anyway)