2003 Serevr DHCP Vendor options

Hi All,

I'm trying to learn how to use Vendor/User class options in 2003.
I need to redirect tftp for my Cisco phones to a different tftp server,
than that defined in the DHCP pools.

So - heres what I've done:

- Right clicked on the server
- Define Vendor Classes
- Add ->
Display Name: Cisco CP-7940
Description: Cisco Systems, Inc. IP Phone CP-7940G
Then ID: Cisco Systems, Inc. IP Phone CP-7940G
- OK
- Set Predefined Options ->
Option Class: Cisco CP-7940
Options name ->
Class: Global
Name: tftp boot
Type: IP Address
Code: 66
Description: Cisco phones boot tftp
Value: 192.168.50.6 (the tftp server).
- OK

Then i've wiresharked the DHCP conversation.
I see the cisco phone passing a Vendor Class ID that seems to match my
setup. I've tried adding ot adding a 0x00 byte to the end, as
wireshark says its 38 characters (and the text is 37), but no success
either way.

I dont think I need to do anything with User classes do I?

In the reply, the option 66 value returned is that of the value set in
"Server Options" for option 66, that I want to use for all other devices.

Thanks for any replies

Adrian


DHCP Discover:

No. Time Source Destination
Protocol Info
1 13:33:08.022863 0.0.0.0 255.255.255.255
DHCP DHCP Request - Transaction ID 0xba8153da

Frame 1 (368 bytes on wire, 368 bytes captured)
Ethernet II, Src: Cisco_81:53:da (00:18:ba:81:53:da), Dst: Broadcast
(ff:ff:ff:ff:ff:ff)
Internet Protocol, Src: 0.0.0.0 (0.0.0.0), Dst: 255.255.255.255
(255.255.255.255)
User Datagram Protocol, Src Port: bootpc (68), Dst Port: bootps (67)
Bootstrap Protocol
Message type: Boot Request (1)
Hardware type: Ethernet
Hardware address length: 6
Hops: 0
Transaction ID: 0xba8153da
Seconds elapsed: 0
Bootp flags: 0x8000 (Broadcast)
Client IP address: 0.0.0.0 (0.0.0.0)
Your (client) IP address: 0.0.0.0 (0.0.0.0)
Next server IP address: 0.0.0.0 (0.0.0.0)
Relay agent IP address: 0.0.0.0 (0.0.0.0)
Client MAC address: Cisco_81:53:da (00:18:ba:81:53:da)
Server host name not given
Boot file name not given
Magic cookie: (OK)
Option: (t=53,l=1) DHCP Message Type = DHCP Request
Option: (53) DHCP Message Type
Length: 1
Value: 03
Option: (t=61,l=7) Client identifier
Option: (61) Client identifier
Length: 7
Value: 010018BA8153DA
Hardware type: Ethernet
Client MAC address: Cisco_81:53:da (00:18:ba:81:53:da)
Option: (t=60,l=38) Vendor class identifier = "Cisco Systems, Inc.
IP Phone CP-7940G"
Option: (60) Vendor class identifier
Length: 38
Value: 436973636F2053797374656D732C20496E632E2049502050...
Option: (t=12,l=15) Host Name = "SIP0018BA8153DA"
Option: (12) Host Name
Length: 15
Value: 534950303031384241383135334441
Option: (t=50,l=4) Requested IP Address = 192.168.57.110
Option: (50) Requested IP Address
Length: 4
Value: C0A8326E
Option: (t=55,l=8) Parameter Request List
Option: (55) Parameter Request List
Length: 8
Value: 014206030F962397
1 = Subnet Mask
66 = TFTP Server Name
6 = Domain Name Server
3 = Router
15 = Domain Name
150 = Private
35 = ARP Cache Timeout
151 = Private
End Option

 

Correction:

I saw that Type: IP Address didnt match the default tftp option of
String, so I changed to that, but still no difference.


Adrian Marsh (NNTP) wrote:
> Hi All,
>
> I'm trying to learn how to use Vendor/User class options in 2003.
> I need to redirect tftp for my Cisco phones to a different tftp server,
> than that defined in the DHCP pools.
>
> So - heres what I've done:
>
> - Right clicked on the server
> - Define Vendor Classes
> - Add ->
> Display Name: Cisco CP-7940
> Description: Cisco Systems, Inc. IP Phone CP-7940G
> Then ID: Cisco Systems, Inc. IP Phone CP-7940G
> - OK
> - Set Predefined Options ->
> Option Class: Cisco CP-7940
> Options name ->
> Class: Global
> Name: tftp boot
> Type: IP Address
> Code: 66
> Description: Cisco phones boot tftp
> Value: 192.168.50.6 (the tftp server).
> - OK
>
> Then i've wiresharked the DHCP conversation.
> I see the cisco phone passing a Vendor Class ID that seems to match my
> setup. I've tried adding ot adding a 0x00 byte to the end, as
> wireshark says its 38 characters (and the text is 37), but no success
> either way.
>
> I dont think I need to do anything with User classes do I?
>
> In the reply, the option 66 value returned is that of the value set in
> "Server Options" for option 66, that I want to use for all other devices.
>
> Thanks for any replies
>
> Adrian
>
>
> DHCP Discover:
>
> No. Time Source Destination Protocol Info
> 1 13:33:08.022863 0.0.0.0 255.255.255.255 DHCP
> DHCP Request - Transaction ID 0xba8153da
>
> Frame 1 (368 bytes on wire, 368 bytes captured)
> Ethernet II, Src: Cisco_81:53:da (00:18:ba:81:53:da), Dst: Broadcast
> (ff:ff:ff:ff:ff:ff)
> Internet Protocol, Src: 0.0.0.0 (0.0.0.0), Dst: 255.255.255.255
> (255.255.255.255)
> User Datagram Protocol, Src Port: bootpc (68), Dst Port: bootps (67)
> Bootstrap Protocol
> Message type: Boot Request (1)
> Hardware type: Ethernet
> Hardware address length: 6
> Hops: 0
> Transaction ID: 0xba8153da
> Seconds elapsed: 0
> Bootp flags: 0x8000 (Broadcast)
> Client IP address: 0.0.0.0 (0.0.0.0)
> Your (client) IP address: 0.0.0.0 (0.0.0.0)
> Next server IP address: 0.0.0.0 (0.0.0.0)
> Relay agent IP address: 0.0.0.0 (0.0.0.0)
> Client MAC address: Cisco_81:53:da (00:18:ba:81:53:da)
> Server host name not given
> Boot file name not given
> Magic cookie: (OK)
> Option: (t=53,l=1) DHCP Message Type = DHCP Request
> Option: (53) DHCP Message Type
> Length: 1
> Value: 03
> Option: (t=61,l=7) Client identifier
> Option: (61) Client identifier
> Length: 7
> Value: 010018BA8153DA
> Hardware type: Ethernet
> Client MAC address: Cisco_81:53:da (00:18:ba:81:53:da)
> Option: (t=60,l=38) Vendor class identifier = "Cisco Systems, Inc.
> IP Phone CP-7940G"
> Option: (60) Vendor class identifier
> Length: 38
> Value: 436973636F2053797374656D732C20496E632E2049502050...
> Option: (t=12,l=15) Host Name = "SIP0018BA8153DA"
> Option: (12) Host Name
> Length: 15
> Value: 534950303031384241383135334441
> Option: (t=50,l=4) Requested IP Address = 192.168.57.110
> Option: (50) Requested IP Address
> Length: 4
> Value: C0A8326E
> Option: (t=55,l=8) Parameter Request List
> Option: (55) Parameter Request List
> Length: 8
> Value: 014206030F962397
> 1 = Subnet Mask
> 66 = TFTP Server Name
> 6 = Domain Name Server
> 3 = Router
> 15 = Domain Name
> 150 = Private
> 35 = ARP Cache Timeout
> 151 = Private
> End Option