Once upon a time, isdtor isdtor@gmail.com said:
11:06:51.413549 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 390) 10.1.2.2.67 > 255.255.255.255.68: [udp sum ok] BOOTP/DHCP, Reply, length 362, xid 0x4007adc6, Flags [Broadcast] (0x8000) Your-IP 10.1.2.57 Server-IP 10.1.2.1 <-- Client-Ethernet-Address 00:1b:21:d8:69:1c file "linux-install/bootx64.efi" Vendor-rfc1048 Extensions Magic Cookie 0x63825363 DHCP-Message Option 53, length 1: ACK Server-ID Option 54, length 4: 10.1.2.2 Lease-Time Option 51, length 4: 43200 Subnet-Mask Option 1, length 4: 255.255.255.0 Default-Gateway Option 3, length 4: 10.1.2.250 Domain-Name-Server Option 6, length 8: 10.1.2.2 Hostname Option 12, length 5: "client" Domain-Name Option 15, length 20: "foo.bar.com" NTP Option 42, length 8: 10.1.2.2 RN Option 58, length 4: 21600 RB Option 59, length 4: 37800 TFTP Option 66, length 11: "10.1.2.1" <-- END Option 255, length 0
I do see a couple of differences - main one is that my boot file is in option 67, not the BOOTP "file" field. Also, my option 66 is a hostname, not an IP. I don't know how you tell ISC DHCP to use option 67 instead of the file field, but maybe that could trigger different client behavior?
More odd is that dnsmasq is adding a null terminator to both options 66 and 67. My UEFI PXE clients seem to accept it just fine though.