Re: [Etherboot-developers] [RFC] Relocation techniques...

[Michael B. <mb...@fe...>]

On Thu, 11 Jul 2002, Peter Lister wrote:
> Anyway, networks being what they are, dropouts are expected and packets
> just get resent. After all, there is no restriction on restarting the
> NFS *server*, right? :)

Yep, done that one.  Accidentally rebooted the server providing / for 120
diskless clients.  All suspended for two minutes and then picked up from
where they left off.  Very impressive.

> > 2a. If you didn't already have a dhcpd.conf then one will have been
> >     created for you based on your network configuration.  Just uncomment
> >     and edit the "range" line and then restart dhcpd.
> > *or*
> > 2b. If you did already have a dhcpd.conf file then just add the line
> >     "include /etc/dhcpd.conf.etherboot.include;" somewhere and restart
> >     dhcpd.
> I'm sure what you have done is fine but I've had practical experience of
> an automatic dhcp configuration which automatically stomped on my dhcp
> config because it was not what the installation "expected". Even
> included files can cause dhcpd to not work, although they limit damage.

I've been fairly careful: the included file doesn't do anything to clients
that aren't Etherboot or udhcpc.  It won't touch your existing config if
you already have one; you have to add the include yourself.

My approach is currently being integrated into Mandrake, according to the
most recent Mandrake Newsletter.

> Extension Path (option 18) should be a much safer way to add dhcp config
> chunks (see recent rant on ltsp-discuss) and need not even be done on
> the machine running the dhcp server. I'll play with the Perl stuff;
> producing raw DHCP options is quite easy, and it should be fairly
> straightfoward to make it emit ISC dhcpd language, so we can have a
> choice.

I've already produced something that does this based on GNU m4.  You can
use the same code to produce either DHCP extension path files or
straightforward ANSI include files.  An example m4 file looks like:

motd(`graphicsmode(80,30,16)`'white`'bgwhite`'cls`'includefile(``backdrop.ansi'')')
menu(`1',``linux'',`Linux',,,,,,`devfs=mount')

Michael Brown
http://www.fensystems.co.uk
--
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