[CentOS] UEFI and PXE

[isdtor]

> Just set up ISC DHCP on fresh CentOS 7 install and followed the redhat
> guide linked in this thread.
> Did what I thought was correct and duplicated the OPs problem.
> /me scratches head. . . off to `tcpdump -vv -nn -i ens192`. . . packets
> never lie. . .
>             Vendor-Class Option 60, length 32:
> "PXEClient:Arch:00007:UNDI:003000"
> 
> d'oh; I did _lower case_ a string in dhcpd.conf line on accident while
> transcribing:
>                 match if substring (option vendor-class-identifier, 0, 9) =
> "pxeclient";
 
Ok, this is not the case here, case is correct, and tcpdump shows that the correct file is requested.

However:

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
11:06:51.413552 IP (tos 0x0, ttl 64, id 64565, offset 0, flags [none], proto UDP (17), length 84)
    10.1.2.57.1943 > 10.1.2.2.69: [udp sum ok]  56 RRQ "linux-install/bootx64.efi" octet tsize 0 blksize 32768    <--

Where: dhcp server = 10.1.2.2, tftp server 10.1.2.1, client 10.1.2.57. DHCP answer is all good and the client still requests the wrong server

I will check if there are any NIC fw updates. If not, the workaround is to move the tftp server to the dhcp server.

And I thought computers were supposed to do my bidding and not the other way round ...