Re: DHCP Problem

Also check that it's not an issue at Layer2... as in that VLAN exists on
both the core and access layer switch. Make sure that voice vlan is
fowarding on your uplink to the core and on your link from the core to the
access layer. (use "show spanning vlan *x *")

I do simlar stuff with routing protocols all the time. "Why isn't my
neighbor coming up?" 5 minutes of scratching my head... "oh, layer 2 is
broken" :)

Chris

On Fri, Apr 24, 2009 at 12:09 AM, Darby Weaver <ccie.weaver_at_gmail.com>wrote:

> Well all points are valid.
>
> You can always perform a debug on dhcp and see what is happening.
>
> Is the server giving out ip addresses? Or is it not?
>
> If you configure device - say your PC or Laptop and configure it for DHCP -
> what happened?
>
> - APIPA?
> - IP Address (Which IP address).
>
> You can have the IP Helper Address on VLAN where the DHCP Server is local
> -
> however it does not accomlish anything for that vlan - since the DHCP
> Request is an Brodcast in the first place and will make it the DHCP Server.
>
> Just a check...
>
> conf t
>
> service dhcp
>
> Is it enabled or disabled?
>
> ===========
>
> Some commands that will help:
>
> Switch#sh ip
> *Mar 1 04:57:51.358: %SYS-5-CONFIG_I: Configured from console by console
> dhcp ?
> binding DHCP address bindings
> conflict DHCP address conflicts
> database DHCP database agents
> import Show Imported Parameters
> limit DHCP limit
> pool DHCP pools information
> relay Miscellaneous DHCP relay information
> server Miscellaneous DHCP server information
> snooping DHCP snooping
> vrf DHCP vrf information
> Switch#sh ip dhcp bind
> Bindings from all pools not associated with VRF:
> IP address Client-ID/ Lease expiration Type
> Hardware address/
> User name
> Switch#sh ip dhcp database
> Switch#sh ip dhcp conflict
> IP address Detection method Detection time VRF
> Switch#
>
> Now I did not see where you disabled conflict logging...
>
> Nor did I hear you mention defining another location to store the database.
>
> You did not supply any debugs to help give some clarity to the scenario.
>
> Hmm....
>
> The Voice VLAN works pretty good configured under the same interface as the
> Data VLAN too.
>
>
> Now there is an old problem I don't see often but I do see.
>
> It has to do with the oder of operations performed when creating a vlan in
> the first place.
>
> And the solution is quick - but you said you can ping the vlan and so I'd
> have to rule that one out.
>
>
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Received on Fri Apr 24 2009 - 19:44:46 ART