On Fri, Jan 3, 2025 at 7:51 AM Chris Novakovic <ch...@chrisn.me.uk> wrote: > > On 03/01/2025 10:40, Lluís Batlle i Rossell wrote: > > here is a patch I used to be able to netboot Raspberry Pi (2B in my case). > > Their bootcode.bin expects a proxy DHCP like for PXE, but it doesn't want a > > filename+sname/tftp_name to fetch a file, but instead it requests DHCP > > Option 66 (TFTP Server) to try to download a wide set of files. > > I don't understand why this patch is necessary - I've netbooted a range > of Raspberry Pis (3B, 3B+, 4B), both with and without proxy DHCP, using > the options that currently exist in Dnsmasq. The most important one is > > dhcp-option=option:tftp-server,<TFTP_IP>
I don't use that. I do use pxe-service=0,"Raspberry Pi Boot" enable-tftp tftp-root=/srv/tftp > > where <TFTP_IP> is the IP address of either the TFTP server if proxy > DHCP is being used or the interface on which Dnsmasq is responding to > the DHCP discover message if not. Dnsmasq won't advertise the TFTP > server in DHCP offers even if its TFTP server function is enabled, but a > suitable dhcp-option line in the Dnsmasq configuration will suffice - it > shouldn't be necessary to force the TFTP server to be advertised (with > dhcp-option-force) because IIRC the Raspberry Pi boot ROM always > requests it in its discover message. > > To netboot old (<= 3B+) Raspberry Pis you'll also need > > dhcp-reply-delay=1 Thanks for that. I hope this is the cause for a mystery problem that seems to come and go for no particular reason. won't hurt to try anyway. > > to compensate for a bug in the boot ROM that causes DHCP responses to be > lost if they're sent too soon after the request. You can gate both of > these options being included in DHCP offers using tags that are set > based either on the MAC address (dhcp-mac) for <= 3B+ devices or on the > DHCP client ID for >= 4B devices. > > The Dnsmasq instance being used as the TFTP server just requires TFTP to > be enabled, and a suitable TFTP root containing bootcode.bin et al to be > set: > > enable-tftp > tftp-root=/path/to/tftp/root > > It might be desirable to serve different TFTP files for each device, in > which case > > tftp-unique-root=mac > > can be used for <= 3B+ devices - the bootloader firmware for >= 4B > devices already has this capability, it just needs to be enabled in the > bootloader configuration. How can I have tftp-root=/path/to/tftp/root/pi for pi and tftp-root=/path/to/tftp/root/x86 for others? that doesn't involve me inventorying all my pi's mac or serial numbers. > > Best wishes, > Chris > > _______________________________________________ > Dnsmasq-discuss mailing list > Dnsmasq-discuss@lists.thekelleys.org.uk > https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss -- Carl K _______________________________________________ Dnsmasq-discuss mailing list Dnsmasq-discuss@lists.thekelleys.org.uk https://lists.thekelleys.org.uk/cgi-bin/mailman/listinfo/dnsmasq-discuss
