On Fri, May 26, 2017 at 12:27:45PM +0300, Andriy Gapon wrote: > On 09/03/2017 08:01, Mariusz Zaborski wrote: > > Author: oshogbo > > Date: Thu Mar 9 06:01:24 2017 > > New Revision: 314948 > > URL: https://svnweb.freebsd.org/changeset/base/314948 > > > > Log: > > Try to extract the RFC1048 data from PXE. If we get enough info we can > > skip > > the bootp(). It removes unnecessary DHCP request from pxeloader. > > > > Submitted by: kczekirda > > Sponsored by: Oktawave > > Initiated by: Matthew Dillon > > Reviewed by: smh, gnn, bapt, oshogbo > > MFC after: 3 weeks > > Differential Revision: https://reviews.freebsd.org/D9847 > > Sorry for being late to the party, but this being head hopefully not too late. > > I am not sure that I agree with the spirit of this change. > > There are network boot setups that do depend on the "unnecessary" DHCP request > from pxeboot. For example, a DHCP server could be configured to return a > different set of parameters depending on a particular PXE client. I > personally > use a configuration where the DCHP server sends a boot menu[*] to a PXE client > that's built into network cards. If a FreeBSD boot is selected and pxeboot is > started, then the server sends parameters required for the FreeBSD boot > (root-path, etc) in response to the request from pxeboot. > I don't see how I can keep that working after this change. > > Additionally, as far as I can tell, we only get cached > PXENV_PACKET_TYPE_BINL_REPLY. This might cause a problem in environments > where > a separate PXE server (Proxy DHCP) is used. In that case the reply might not > have the network configuration information which would actually be in > PXENV_PACKET_TYPE_DHCP_ACK. > An example of such a setup is described here: > https://n0dy.com/blog/2014/09/14/network-booting-with-dnsmasq-in-proxy-mode/ > Using a separate PXE server is not uncommon in corporate environments too. > > In general, I think that the change was not thought through to cover scenarios > beyond the basic unattended, FreeBSD-only, single DHCP server network boots. > That scenario is, of course, very common, but it is not the only one. > > At minimum, I would like to have a compile time option to control whether > pxeboot should send a DHCP request of its own or rely entirely on the cached > information. Or maybe pxeboot could be smart enough to do the former if the > cached reply is missing some required information like the root-path. > Right now, there is no bootp(BOOTP_PXE) under any conditions. > > And my apologies again for missing the original discussion. > My focus was somewhere else at the time. > > [*] It uses PXE_BOOT_MENU and PXE_MENU_PROMPT vendor options for that. > > References: > http://www.pix.net/software/pxeboot/archive/pxespec.pdf
I should have been all fixed in head (including some sugar added) Can you confirm? Best regards, Bapt
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