DHCPD , dhcp relays on a large network
Alexandru Coseru
alexandru.coseru at totaltelecom.ro
Fri Nov 10 12:09:02 UTC 2006
The ideea is that each switch has a subnet attached to it..
On the backbone , I have the dhcpd server..
The dhcpd server is not directly attached to the subnets , it has to go
through a layer3 route to reach them..
10.1.1.0/24 192.168.1.0/24
srv1 ---------------- L3 SW A -------------------------
subnet1
The L3 SW A has DHCPD relay options enabled , so the DHCPD requests
arrives on srv1.
But srv1 has no knowledge of class 192.168.1.0/24 , and the server
cannot be started (Error: No subnet declaration for 192.168.1.0/24).
The server has only one ethernet NIC , with ip 10.1.1.1 on it..
Can you elaborate more on shared networks ?
Regards
Alex
----- Original Message -----
From: "Randy Grimshaw" <rgrimsha at syr.edu>
To: <dhcp-users at isc.org>
Sent: Friday, November 10, 2006 5:29 AM
Subject: Re: DHCPD , dhcp relays on a large network
> alexandru:
> In your example the dhcp server does not need to be aware of the
> vlans - that is being handled by your switches. Because they are acting
> as bootp helpers right? It sounds like you need to review your
> configuration for subnets. I suspect you may have more shared nets than
> you realize.
> <><Randy
>
>
>
> <><Randall Grimshaw
> Room 203 Machinery Hall
> Syracuse University
> Syracuse, NY 13244
> 315-443-5779
> rgrimsha at syr.edu
>>>> alexandru.coseru at totaltelecom.ro 11/09/06 5:55 PM >>>
> Content-Type: text/plain;
> charset="iso-8859-1"
> Content-Transfer-Encoding: quoted-printable
> Hello..
>
> I have a large network with a couple of subnets and i want to configure
> =
> a DHCPD server to lease IP addresses to clients , connected through =
> layer3 switches with relay agents on them.
>
>
> Attached is a small representation (no of l3 switches reduced , to =
> make it easier to understand).
>
>
> On each switch I have some subnets , each one assigned to a specific =
> VLAN.
> Between switches , I'm running OSPF , linked with quagga on srv1 =
> (configured as ASBR) , which is also an internet router (running bgpd =
> with several ISPs).
>
>
> Srv1: has ip address 10.1.1.1 on VLAN 2. The switches have IP =
> 10.1.1.x , on VLAN 2 also... This VLAN is used for management and =
> OSPF..
> Each switch has an VLAN2 address and a specific VLAN assigned to the =
> clients subnet. VLAN10,VLAN11 , VLAN12 , etc....
>
>
> When I'm trying to declare all subnets in dhcpd.conf , i have the =
> following error: No subnet declaration for xxxxx.
>
> I cannot define aliases on the srv1 , cause it will break the internet =
> routing...
>
> What should I do ?
>
> a) Install an separate server for DHCPD and define eth0:1 =
> 192.168.1.1/24 eth0:2 192.168.2.1/24 , etc on it ?
> b) Declare a subnet of 192.168.0.0/ 255.255.0.0 in dhcpd.conf ?
>
>
> Thanks
> Alex
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
> --
> No virus found in this incoming message.
> Checked by AVG Free Edition.
> Version: 7.1.409 / Virus Database: 268.14.1/527 - Release Date: 11/9/2006
>
>
More information about the dhcp-users
mailing list