Mailing List Archive

Procurve DHCP relay question
I'm in the middle of a transition from HP -> Cisco, with an HP 2848 as the
"core", so sorry if this e-mail is off topic. I am having a hard time
getting DHCP relay to work, and was hoping someone with HP experience could
chime in with some assistance.

I've created a new VLAN, and have specified a helper-address to point to a
DHCP server that manages dozens of scopes. The new VLAN functions fine,
assuming users are given a static address, but DHCP does not appear to work
at all.

To troubleshoot I pointed the helper-address to a system with Wireshark, but
I don't see any requests coming in when a user on the new VLAN requests a
new DHCP address, indicating that the request is not being forwarded
properly. Is there any debugging available on the procurve to troubleshoot
this further?

I've read a number of documents describing how to configure DHCP relay on a
procurve, and as far as I can tell the recommendations match my
configuration.

Here are the features enabled on the 2848:
- 'ip routing' is enabled
- 'dhcp-relay' does not show in a 'show run', indicating it is enabled (the
default)
- A 'ip helper-address x.x.x.x' statement is configured on the VLAN
interface
- There is a route back to the destination helper-address
- Connectivity works on the VLAN in question, assuming users are statically
configured

Any advice would be appreciated..

-- Eric Cables
_______________________________________________
cisco-nsp mailing list cisco-nsp@puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: Procurve DHCP relay question [ In reply to ]
Eric Cables wrote:
> I'm in the middle of a transition from HP -> Cisco, with an HP 2848 as the
> "core", so sorry if this e-mail is off topic. I am having a hard time
> getting DHCP relay to work, and was hoping someone with HP experience could
> chime in with some assistance.
>
> I've created a new VLAN, and have specified a helper-address to point to a
> DHCP server that manages dozens of scopes. The new VLAN functions fine,
> assuming users are given a static address, but DHCP does not appear to work
> at all.
>
> To troubleshoot I pointed the helper-address to a system with Wireshark, but
> I don't see any requests coming in when a user on the new VLAN requests a
> new DHCP address, indicating that the request is not being forwarded
> properly. Is there any debugging available on the procurve to troubleshoot
> this further?
>
> I've read a number of documents describing how to configure DHCP relay on a
> procurve, and as far as I can tell the recommendations match my
> configuration.
>
> Here are the features enabled on the 2848:
> - 'ip routing' is enabled
> - 'dhcp-relay' does not show in a 'show run', indicating it is enabled (the
> default)
> - A 'ip helper-address x.x.x.x' statement is configured on the VLAN
> interface
> - There is a route back to the destination helper-address
> - Connectivity works on the VLAN in question, assuming users are statically
> configured

I've got a 'J4904A' HP ProCurve 2848 that I can do some quick testing
with...

Can you provide a 'sh run' from both units? Also specify what type of
Cisco you are running, and its version.

Is this simply a replacement of a switch you are trying to achieve?

Steve
_______________________________________________
cisco-nsp mailing list cisco-nsp@puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: Procurve DHCP relay question [ In reply to ]
On Thu, 8 Jan 2009, Eric Cables wrote:
> I'm in the middle of a transition from HP -> Cisco, with an HP 2848 as the
> "core", so sorry if this e-mail is off topic. I am having a hard time
> getting DHCP relay to work, and was hoping someone with HP experience could
> chime in with some assistance.
>
> I've created a new VLAN, and have specified a helper-address to point to a
> DHCP server that manages dozens of scopes. The new VLAN functions fine,
> assuming users are given a static address, but DHCP does not appear to work
> at all.


Hi Eric,

I'm not sure how helpful this might be (it seems you've already taken the
necessary steps), but here's a cut and paste from a production switch
doing the same thing (a 5400 in this case):

vlan 4071
name "VLAN4071"
ip helper-address 10.144.16.2
ip address 10.144.1.65 255.255.255.192
tagged A1-A4,Trk1
exit

HTH,
-j

--
Jeremy L. Gaddis
http://evilrouters.net

_______________________________________________
cisco-nsp mailing list cisco-nsp@puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: Procurve DHCP relay question [ In reply to ]
Thanks all for the feedback. Turns out the software revision on the
switch (0.8.58) was part of a revision window that had dhcp relay OFF
by default. I upgraded to the latest revision, which had it enabled.

On 1/9/09, Jeremy L. Gaddis <jeremy@evilrouters.net> wrote:
> On Thu, 8 Jan 2009, Eric Cables wrote:
>> I'm in the middle of a transition from HP -> Cisco, with an HP 2848 as the
>> "core", so sorry if this e-mail is off topic. I am having a hard time
>> getting DHCP relay to work, and was hoping someone with HP experience
>> could
>> chime in with some assistance.
>>
>> I've created a new VLAN, and have specified a helper-address to point to a
>> DHCP server that manages dozens of scopes. The new VLAN functions fine,
>> assuming users are given a static address, but DHCP does not appear to
>> work
>> at all.
>
>
> Hi Eric,
>
> I'm not sure how helpful this might be (it seems you've already taken the
> necessary steps), but here's a cut and paste from a production switch
> doing the same thing (a 5400 in this case):
>
> vlan 4071
> name "VLAN4071"
> ip helper-address 10.144.16.2
> ip address 10.144.1.65 255.255.255.192
> tagged A1-A4,Trk1
> exit
>
> HTH,
> -j
>
> --
> Jeremy L. Gaddis
> http://evilrouters.net
>
>

--
Sent from my mobile device


-- Eric Cables
_______________________________________________
cisco-nsp mailing list cisco-nsp@puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/
Re: Procurve DHCP relay question [ In reply to ]
That's great to hear Eric!

I ran into some DHCP issues when using MAC authentication over RADIUS
on a 5412zl this summer. In my case a simple software upgrade did the
trick as well!

- Chris

> Message: 3
> Date: Sun, 11 Jan 2009 11:28:15 -0600
> From: "Eric Cables" <ecables@gmail.com>
> Subject: Re: [c-nsp] Procurve DHCP relay question
> To: "Jeremy L. Gaddis" <jeremy@evilrouters.net>,
> "cisco-nsp@puck.nether.net" <cisco-nsp@puck.nether.net>
> Message-ID:
> <d5c7ccac0901110928j2c7e216cx9079c008043c18bb@mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> Thanks all for the feedback. Turns out the software revision on the
> switch (0.8.58) was part of a revision window that had dhcp relay OFF
> by default. I upgraded to the latest revision, which had it enabled.
>
> On 1/9/09, Jeremy L. Gaddis <jeremy@evilrouters.net> wrote:
>> On Thu, 8 Jan 2009, Eric Cables wrote:
>>> I'm in the middle of a transition from HP -> Cisco, with an HP 2848 as the
>>> "core", so sorry if this e-mail is off topic. I am having a hard time
>>> getting DHCP relay to work, and was hoping someone with HP experience
>>> could
>>> chime in with some assistance.
>>>
>>> I've created a new VLAN, and have specified a helper-address to point to a
>>> DHCP server that manages dozens of scopes. The new VLAN functions fine,
>>> assuming users are given a static address, but DHCP does not appear to
>>> work
>>> at all.
>>
>>
>> Hi Eric,
>>
>> I'm not sure how helpful this might be (it seems you've already taken the
>> necessary steps), but here's a cut and paste from a production switch
>> doing the same thing (a 5400 in this case):
>>
>> vlan 4071
>> name "VLAN4071"
>> ip helper-address 10.144.16.2
>> ip address 10.144.1.65 255.255.255.192
>> tagged A1-A4,Trk1
>> exit
>>
>> HTH,
>> -j
>>
>> --
>> Jeremy L. Gaddis
>> http://evilrouters.net
>>
>>
>
> --
> Sent from my mobile device
>
>
> -- Eric Cables
_______________________________________________
cisco-nsp mailing list cisco-nsp@puck.nether.net
https://puck.nether.net/mailman/listinfo/cisco-nsp
archive at http://puck.nether.net/pipermail/cisco-nsp/