<html><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class="">Hi,<div class=""><br class=""></div><div class="">Raspberry Pi CM4 sends its serial as part of Option 97 but I cannot find a way to get hold of this value in my <b class="">dnsmasq</b> hook script.</div><div class=""><br class=""></div><div class=""><b class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>Does anyone know if this is currently possible or if it would require a code change?</b></div><div class=""><br class=""></div><div class="">Note that I do find a reference to Option 97 in the dnsmasq logs, but this value is truncated. Also it is sent as part of the DHCPOFFER, which seems a bit backwards as I would expect the client send this to the server and not the other way around.</div><div class=""><br class=""></div><div class=""><b class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>Is dnsmasq just echoing back what was by the client or is it creating its own id?</b></div><div class=""><br class=""></div><div class="">Best regards,</div><div class=""><br class=""></div><div class="">Christoffer</div><div class=""><div class=""><br class=""></div><div class="">PS I have also posted a version of this question on the [Raspberry Pi](<a href="https://raspberrypi.stackexchange.com/q/135324/143240" class="">https://raspberrypi.stackexchange.com/q/135324/143240</a>) and will update it accordingly with any relevant answers I might get here!</div><div class=""><br class=""></div><div class="">PPS My hope is to provision the correct TFTP files and NFS share for the next stages of the PXE/netboot process that will be specific to each Raspberry. During this process Pi will request TFTP files with the serial as part of the the path, e.g. </div><div class=""><div class=""><br class=""></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>/ac78de89/start4.elf</div><div class=""><br class=""></div><div class="">… where ac78de89 is the serial id.</div><div class=""><br class=""></div></div><div class=""><div class="">According to Raspberry Pi issues discussd on Github (cf. <a href="https://github.com/raspberrypi/rpi-eeprom/issues/182#issuecomment-657069276" class="">https://github.com/raspberrypi/rpi-eeprom/issues/182#issuecomment-657069276</a>) the DHCP option 97 sent by the client should contain "<i class="">a combination of 0x34695052 (RPi4 as 4 bytes, backwards), the board revision (so you can detect the exact model, ram, and everything), part of the mac, and the full serial#</i>”.</div><div class=""><br class=""></div><div class=""><br class=""></div></div></div></body></html>