[Kea-users] "filename" vs "option bootfile-name"

[Patrik Lundin]

On Sun, Jul 10, 2016 at 05:18:39PM +0000, Francis Dupont wrote:
>
> you can see further text about "overload". But this 19 year old text
> doesn't match the current use: tftp-server-name and bootfile-name
> options are less ambiguous, have no silly length limits, etc, than
> BOOTP fields. But if you have another opinion with good arguments
> you can ask for a feature for setting sname and file fields.
> (and this list is the right place to discuss about this kind of things)
>

I do not currently have such arguments. Just knowing that this is the
current stance of the kea project is enough for me to take this up with
the OpenBSD people instead.

To be honest the "sname" makes me even more confused as to what it is
supposed to be used for. RFC 2131 mentions nothing about how it should
be used (the only mentions it gets is related to that it may be
overladed with options) and the BOOTP RFC 951 only seems to use it as
something sent by the client, not by the server:
===
If the client wishes to restrict booting to a particular server
name, it may place a null-terminated string in 'sname'.  The name
used should be any of the allowable names or nicknames of the
desired host.
===

It further gives examples of how the BOOTP server may react when it gets
a BOOTREQUEST with the sname filled in.

Yet dhcpd.conf allows the setting of server-name on the server side:
===
The server-name statement can be used to inform the client of the name of the
server from which it is booting.
===

It seems like undefined behaviour as to what clients should do when they
recieve a message with sname (or its tftp-server-name counterpart) set.
It seems more like "some additional information regarding the server
that the client may filter responses on" than a "download the file from
here" option which siaddr is cleary defined as.

Lots of headscratching for me today :).

Anyway, like I said I will accept the fact that kea considers "file"
deprecated in favor of the boot-file-name option. It just means the
autoinstall feature of OpenBSD needs to know about it as well.

-- 
Patrik Lundin