DHCP Option(s) 66 and 67 on ASUS Router?

Spyder1384 · August 14, 2019

I'm trying to find a way to set my home network up to allow for PXE boot, but am trying to do so without the need for additional DHCP aside from my router.

The router is an ASUS GT-AC5300 so I know I'm able to use CLI via PuTTy. I'm just not overly familiar with the CLI environment of the router.

Pretty sure the only thing I need to be able to do is have DHCP define Options 66/67 to make this work the way I'm wanting.

Any help would be appreciated.

Slayerking92 · August 15, 2019

DHCP on consumer routers are fairly limited. If the manual doesn't provide an answer, chances are, it isn't supported without a custom firmware.

Spyder1384 · August 22, 2019

Thanks for the reply. That's mostly what I had figured. I know the RT-AC5300 has open source firmware, but I'm not sure how open the firmware is on the GT-AC5300. I've used PuTTY for a couple permissions settings for USB drive access, but that's about it. Was hoping someone might be a bit more familiar with modifying the firmware through CLI. Anyhow, thanks again.

GreivinV · January 20, 2022

SSH from Asus routers is not flexible.

I worked this around using pihole. Here is a copy of my setup.

In my case arch7, and arch9 are optional, but if the server that you are PXE booting to, requires it, here is the example.
After saving the file, you need to reload the service.
If someone finds a way to push these settings to dnsmasq on an Asus router, I would appreciate the contribution.
(the server I am PXE booting to is 192.168.1.6)

pi@raspberrypi:/etc/dnsmasq.d $ cat 02-pihole-dhcp.conf

###############################################################################

# DHCP SERVER CONFIG FILE AUTOMATICALLY POPULATED BY PI-HOLE WEB INTERFACE. #

# ANY CHANGES MADE TO THIS FILE WILL BE LOST ON CHANGE #

###############################################################################

dhcp-authoritative

dhcp-range=192.168.1.15,192.168.1.253,24h

dhcp-option=option:router,192.168.1.1

dhcp-leasefile=/etc/pihole/dhcp.leases

#PXE

dhcp-option=66,"192.168.1.6"

dhcp-boot=ipxe.efi,,192.168.1.6

dhcp-match=set:efi-x86_64,option:client-arch,7

dhcp-match=set:efi-x86_64,option:client-arch,9

#quiet-dhcp

domain=scuarmander.com

local=/scuarmander.local/

pi@raspberrypi:/etc/dnsmasq.d $ sudo service pihole-FTL reload

jec6613 · January 20, 2022

On 8/14/2019 at 5:23 PM, Spyder1384 said:

Pretty sure the only thing I need to be able to do is have DHCP define Options 66/67 to make this work the way I'm wanting.

Depends on your PXE server, some will handle it within a broadcast domain. That being said, you have a PXE server and all of the TFTP and such that that entails, why not just run DHCP on that server?