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@NiKiZe
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Trying to chainload iPXE with full feature set from a lesser featured one. dnsmasq ProxyDHCP edition
# Known working dnsmasq version 2.85 config for iPXE proxydhcp usage
# things to replace:
# * 10.1.1.0 - your subnet
# * eth0 - interface to listen on, or switch to bind-dynamic
# * 10.1.1.2 - your tftp server ip
# * http://gentoo.ipxe.se/boot.ipxe - script to run once inside iPXE
# Debug logging
log-debug
# Disable DNS server
port=0
# send disable multicast and broadcast discovery, and to download the boot file immediately
# DHCP_PXE_DISCOVERY_CONTROL, should be vendor option? Needs more understanding and source
dhcp-option=vendor:PXEClient,6,2b
# This range(s) is for the public interface, where dnsmasq functions
# as a proxy DHCP server providing boot information but no IP leases.
# Any ip in the subnet will do, so you may just put your server NIC ip here.
dhcp-range=10.1.1.0,proxy
interface=eth0
# bind-dynamic - remove interface and use this instead to listen everywhere?
# Disable re-use of the DHCP servername and filename fields as extra
# option space. That's to avoid confusing some old or broken DHCP clients.
dhcp-no-override
#dhcp-match=set:<tag>,<option number>|option:<option name>|vi-encap:<enterprise>[,<value>]
#dhcp-boot=[tag:<tag>,]<filename>,[<servername>[,<server address>|<tftp_servername>]]
# Based on logic in https://gist.github.com/robinsmidsrod/4008017
# iPXE sends a 175 option, checking suboptions
dhcp-match=set:ipxe-http,175,19
dhcp-match=set:ipxe-https,175,20
dhcp-match=set:ipxe-menu,175,39
dhcp-match=set:ipxe-pxe,175,33
dhcp-match=set:ipxe-bzimage,175,24
dhcp-match=set:ipxe-iscsi,175,17
dhcp-match=set:ipxe-efi,175,36
# set ipxe-ok tag if we have correct combination
# http && menu && iscsi ((pxe && bzimage) || efi)
tag-if=set:ipxe-ok,tag:ipxe-http,tag:ipxe-menu,tag:ipxe-iscsi,tag:ipxe-pxe,tag:ipxe-bzimage
tag-if=set:ipxe-ok,tag:ipxe-http,tag:ipxe-menu,tag:ipxe-iscsi,tag:ipxe-efi
#pxe-service=[tag:<tag>,]<CSA>,<menu text>[,<basename>|<bootservicetype>][,<server address>|<server_name>]
#pxe-prompt=[tag:<tag>,]<prompt>[,<timeout>]
# these create option 43 cruft, which is required in proxy mode
# TFTP IP is required on all dhcp-boot lines (unless dnsmasq itself acts as tftp server?)
pxe-service=tag:!ipxe-ok,X86PC,PXE,undionly.kpxe,10.1.1.2
pxe-service=tag:!ipxe-ok,IA32_EFI,PXE,snponlyx32.efi,10.1.1.2
pxe-service=tag:!ipxe-ok,BC_EFI,PXE,snponly.efi,10.1.1.2
pxe-service=tag:!ipxe-ok,X86-64_EFI,PXE,snponly.efi,10.1.1.2
# later match overrides previous, keep ipxe script last
# server address must be non zero, but can be anything as long as iPXE script is not fetched over TFTP
dhcp-boot=tag:ipxe-ok,http://gentoo.ipxe.se/boot.ipxe,,0.0.0.1
# To use internal TFTP server enabled these, recommended is otherwise atftp
#enable-tftp
#tftp-root=/tftproot/
@robinsmidsrod
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@NiKiZe When I created that example, iSCSI support for EFI didn't exist, hence why it wasn't in that build. ;)

Good job on the proxydhcp setup. Can imagine that is useful for people that have minimal way to configure their existing DHCP server.

@NiKiZe
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NiKiZe commented Aug 6, 2021

Yes I know, just realized that iSCSI is default now so made that change.

I much prefer dhcpd, just that when you can't modify existing DHCP this is what you need to resort to :/
(even started to look into a freestanding iPXE proxydhcp solution, but in the end got this working, even tho I don't like the menu.)

@robinsmidsrod
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robinsmidsrod commented Aug 6, 2021

I seem to recall seeing someone trying to implement a DHCP server in Go, primarily for network-booting. Not sure what it was called, but Konobi might've been involved. There is also this Perl CPAN package, https://metacpan.org/pod/Net::DHCP::Packet, that I thought of using at some point to create something, but I never found the time...

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