Re: [Etherboot-developers] DHCP option 175

[<ke...@us...>]

>In my opinion, ASCII text is always preferred. For DHCPD maintainence
>binary data is not a good idea ! And the byte space is definitive not
>critical in this point (3 or 8 bytes ....)

ISC DHCPD's facilities for representing strings is just as good that for
text. Text is just a special case of string where the components are
chars in quotes instead of hex values.

>Normally an admin should know the components, ...

The whole idea is for the admin to need to know less.

>The string (option 175) must be very clear and simple,
>and in my opinion TEXT.

A unjustified bias. Humans will not read the option. It will be used to
direct automatic tools. Say perhaps of a smart DHCPD that can
interpolate values into the filename string, which can then trigger a
smart TFTPD to build an image on the fly.

>Using PCI ID is perhaps not the best idea ! Perhaps it is a
>better idea to give "keywords" at boot ROM compile time,
>which is passed as tag 175.

The whole idea is not to have to specify anything. The code just passes
the information up to the DHCP server and the software
selects/constructs the right image.

This complements the method used by LTSP which is a probe from a
ramdisk.  In some uses of Etherboot, having to boot a kernel to
determine what module to load, may be too heavyweight. This ID mechanism
can also be used by other operating systems.