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DHCP server not working for iPXE

DHCP server not working for iPXE

excessive
New Contributor

The switch is BlackDiamond X8.
I’ve set dhcp server for our lab VLAN that I’m using for testing. The pool range and everything else works as intended.
I’ve configured options 66 and 67 to FOG server machine and that’s where it breaks. I’m getting:

Filename: undionly.kpxe
Could not start download: Operation not supported (http://ipxe.org/3c092003)

 

I can confirm that when using separate isc-dhcp server there’s no problem. But I’d like to utilize our switch.

Here’s snippet of my configuration:

VLAN "XXX_TEST":
    DHCP Address Range   : 192.168.xx.xx->192.168.xx.xx
    Netlogin Lease Timer : Not configured (Default = 10 seconds)
    DHCP Lease Timer     : 86400 seconds
    Default Gateway      : 192.168.xx.xx
    Primary DNS Server   : xx.xx.xx.xx
    DHCP Option Code  66 : ipaddress 192.168.xx.xx
    DHCP Option Code  67 : string "undionly.kpxe"
    Ports DHCP Enabled   : 1:21

29 REPLIES 29

excessive
New Contributor

I don’t have significant experience with Wireshark, but I’m doing exactly the same thing as I did with my working scenario. Just filtering everything with “bootp”. I’m capturing those frames using a Windows machine on the same subnet with interface in promiscuous mode.

StephanH
Valued Contributor III

Hmm, if a client get an ip address from an dhcp all for packets I wrote have to be here. Therefore the packets are missing in your trace. Discover and Request go into the same direction. Maybe you are logging only one direction?

Regards Stephan

excessive
New Contributor

Indeed, I wrote this and I can confirm that it works. I’ve set different range of addresses for both scenarios and right now the computer in front of me is working with ip address received from the pool of the switch (192.168.230.200 - 192.168.230.220). I realize how strange it may look, but that’s how it is.

StephanH
Valued Contributor III

Hello,

in your first post you wrote:

I’ve set dhcp server for our lab VLAN that I’m using for testing. The pool range and everything else works as intended.


so I assumed that except for the two DHCP option DHCP works with XOS and the client receive a ip from the XOS DHCP. However, according to your last information, the client does not get an address from the DHCP server on the XOS switch. Is that correct?
I.e. the client has never received IP addresses from DHCP on the XOS switch, right?

Normaly you should see in both cases.

  1. Discover
  2. Offer
  3. Request
  4. ACK
Regards Stephan

excessive
New Contributor

Managed to capture some frames.
On the working scenario I have DISCOVER and OFFER packets passing.
Here’s some output:

 

Frame 475: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits) on interface \Device\NPF_{4C63F991-A548-48B3-A772-5278B943AE7F}, id 0
Ethernet II, Src: e6:95:01:b5:0a:4e (e6:95:01:b5:0a:4e), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 192.168.230.51, Dst: 255.255.255.255
User Datagram Protocol, Src Port: 67, Dst Port: 68
Dynamic Host Configuration Protocol (Offer)
Message type: Boot Reply (2)
Hardware type: Ethernet (0x01)
Hardware address length: 6
Hops: 0
Transaction ID: 0x9f77d344
Seconds elapsed: 10
Bootp flags: 0x8000, Broadcast flag (Broadcast)
Client IP address: 0.0.0.0
Your (client) IP address: 192.168.230.170
Next server IP address: 192.168.230.51
Relay agent IP address: 0.0.0.0
Client MAC address: 82:5d:c6:8a:7e:48 (82:5d:c6:8a:7e:48)
Client hardware address padding: 00000000000000000000
Server host name not given
Boot file name: undionly.kpxe
Magic cookie: DHCP
Option: (53) DHCP Message Type (Offer)
Option: (54) DHCP Server Identifier (192.168.230.51)
Option: (51) IP Address Lease Time
Option: (1) Subnet Mask (255.255.255.0)
Option: (3) Router
Option: (6) Domain Name Server
Option: (15) Domain Name
Option: (255) End
Padding: 00000000000000000000000000000000

 

 

 

And here having the switch as DHCP I can see only two DISCOVER packets and one Request to which there seems to be no response at all.

 

Frame 370: 449 bytes on wire (3592 bits), 449 bytes captured (3592 bits) on interface \Device\NPF_{4C63F991-A548-48B3-A772-5278B943AE7F}, id 0
Ethernet II, Src: 82:5d:c6:8a:7e:48 (82:5d:c6:8a:7e:48), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255
User Datagram Protocol, Src Port: 68, Dst Port: 67
Dynamic Host Configuration Protocol (Request)
Message type: Boot Request (1)
Hardware type: Ethernet (0x01)
Hardware address length: 6
Hops: 0
Transaction ID: 0xa41b0d65
Seconds elapsed: 14
Bootp flags: 0x0000 (Unicast)
Client IP address: 0.0.0.0
Your (client) IP address: 0.0.0.0
Next server IP address: 0.0.0.0
Relay agent IP address: 0.0.0.0
Client MAC address: 82:5d:c6:8a:7e:48 (82:5d:c6:8a:7e:48)
Client hardware address padding: 00000000000000000000
Server host name not given
Boot file name not given
Magic cookie: DHCP
Option: (53) DHCP Message Type (Request)
Option: (57) Maximum DHCP Message Size
Option: (93) Client System Architecture
Option: (94) Client Network Device Interface
Option: (60) Vendor class identifier
Option: (77) User Class Information
Option: (55) Parameter Request List
Option: (175) Etherboot
Option: (61) Client identifier
Option: (97) UUID/GUID-based Client Identifier
Option: (54) DHCP Server Identifier (192.168.230.253)
Option: (50) Requested IP Address (192.168.230.200)
Option: (255) End

 

 

Let me know if this helps or I should provide more data.

GTM-P2G8KFN