Just trying rpi4 netboot - June 2020 stable version. Nice work - thank you!
I see that the DHCP DISCOVER message reports a 'Client System Architecture' (option 93, 0x5d) of 'IA x86 PC' (numeric value 0). This can cause some confusion on mixed architecture networks.
Can this be changed to an Arm-appropriate value - or, better yet, made into a configuration option?
Thanks again.
Re: RPi4 Netboot - DHCP option 93
Please can you raise an rpi-eepom Github issue describing exactly what DHCPconfigurations are affected by this?
The PXE protocol in Raspberry Pi network boot is only used as a convenient method for discovering the appropriate DHCP server, there's no intention to actually do PXE so it's not clear why the client architecture should matter. That said if switching for X86 to something else fixes something and doesn't cause regressions (i.e. doesn't break PiServer or similar) then I have no objections to such a change.
My preference would be to make this a non-configurable change in order to avoid adding more configuration bloat to the bootloader which is why I'd like to give others the chance to comment on this in the unlikely event that it causes a regression.
The PXE protocol in Raspberry Pi network boot is only used as a convenient method for discovering the appropriate DHCP server, there's no intention to actually do PXE so it's not clear why the client architecture should matter. That said if switching for X86 to something else fixes something and doesn't cause regressions (i.e. doesn't break PiServer or similar) then I have no objections to such a change.
My preference would be to make this a non-configurable change in order to avoid adding more configuration bloat to the bootloader which is why I'd like to give others the chance to comment on this in the unlikely event that it causes a regression.
Re: RPi4 Netboot - DHCP option 93
Yeah, and I do wish you wouldn't call it PXE for that reason. It isn't PXE: that's an x86 thing; it downloads an x86 (16b!) real-mode blob and executes it, with the BIOS extension ROM providing some hooks for it to send and receive IPv4 packets via the network card. The Pi does network booting, of the sort that Sun, SGI, and everybody else has been doing for decades (initially with RARP / BOOTP, later DHCP, and TFTP).
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cleverca22
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Re: RPi4 Netboot - DHCP option 93
when you do open an issue, can you link it here? i have some other thoughts on the netboot stuff, and how it handles the dhcp reply that could be added to the ticket
Re: RPi4 Netboot - DHCP option 93
What would you set it to anyway? None of the processor architecture type IDs for option 93 in the IANA registry match what the Pi is doing. It isn't using UEFI or U-boot and it needs its firmware + overlays + config loaded first.
Changing option 93 will break any existing Pi netboot setups including PiServer as the dnsmasq configuration is expecting type 0 aka x86PC. They'll need to apply a patch to the configuration to add a pxe-service line for the new type ID.
Changing option 93 will break any existing Pi netboot setups including PiServer as the dnsmasq configuration is expecting type 0 aka x86PC. They'll need to apply a patch to the configuration to add a pxe-service line for the new type ID.
Re: RPi4 Netboot - DHCP option 93
Github issue posted here https://github.com/raspberrypi/rpi-eeprom/issues/182 as requested.
As noted, there is no IANA assignment correpsonding to the rpi, and changing the default would break existing setups - but I also understand the desire to avoid configuration bloat!
As noted, there is no IANA assignment correpsonding to the rpi, and changing the default would break existing setups - but I also understand the desire to avoid configuration bloat!