[c-nsp] cisco-nsp Digest, Vol 74, Issue 20

[Eric Cables]

I haven't updated the sw yet, maybe that will yield some results.  I have
confirmed that I can ping the DHCP server from the switch, and vice versa.

I'll check out the software image, and see how behind it is.

Thanks for the tips..

-- Eric Cables


On Fri, Jan 9, 2009 at 3:30 PM, Chris Burwell <cburwell at gmail.com> wrote:

> Hi Eric,
>
> There are a few basic things that should be checked first. I don't
> mean to insult anyone, but I sometimes overlook some simple steps when
> I dive into a problem.
>
> First, ensure you have the latest software (as HP calls it) running on
> the switch. This is freely available from the Procurve website (no
> login is needed).
>
> Second, console into the switch and see if you can ping the DHCP
> server from the command prompt. If you cannot, then the switch does
> not know how to reach the DHCP server.
>
> Finally, check to see that you have the proper route for the VLAN on
> the switch. For example on our core 8212zl, I have to add the
> following statement for each VLAN:
>
> vlan 800
>    ip ospf 192.168.0.1 area 0.0.0.1
> exit
>
> Obviously this is the statement used for OSPF on an 8212zl, so your
> config might be different (particularly if you're using a different
> routing protocol.
>
> - Chris
>
> > Date: Thu, 8 Jan 2009 13:52:50 -0800
> > From: "Eric Cables" <ecables at gmail.com>
> > Subject: [c-nsp] Procurve DHCP relay question
> > To: "cisco-nsp at puck.nether.net" <cisco-nsp at puck.nether.net>
> > Message-ID:
> >        <d5c7ccac0901081352w1e492fadg61d3edbdc1fcc67c at mail.gmail.com>
> > Content-Type: text/plain; charset=ISO-8859-1
> >
> > 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
>