DHCP filter by MAC address possible?

[Tim Roelands]

Hi!

Using a Cisco 800 series router we would like to fine tune the configured DHCP server for IP phone use. IP Phones get there profile by using Auto Provisioning (AP). Every brand has it's own AP profile path trough option 66 (TFTP). So DHCP provides the IP phones the correct TFTP path. Problem is there will be added a bunch of new IP phones (different brand) to the existing network. These new phones require a different TFTP path for AP than the existing IP phones.

Using the DHCP configuration it's only possible to configure just one option 66 to the DHCP. Is it possible to provide the IP phones there own Option 66 using the same DHCP server? Like adding a MAC filter to the DHCP where IP phones that start with MAC address 00-04-F2.x.x.x get Option 66 to location A and IP phones that start with MAC 00-05-F6.x.x.x get Option 66 to location B.

I would like to prevent using VLAN's. All other options are welcome!

[paul driver]

Hello

I have never done this however have you read this CCO document-

here

res

Paul

[ghostinthenet]

You can, but you have to use DHCP reservations to do it. If you were using a server-based DHCP solution, like ISC dhcpd, you could definitely filter by MAC OUI as you propose, but router-based DHCP is a bit more limited. On the router, for each phone, you would set up a host pool, like this:

ip dhcp pool DHCP_Pool_LAN
 network 172.16.0.0 255.255.252.0
 default-router 172.16.0.1 
 dns-server 8.8.8.8 8.8.4.4 
 option 66 ascii "172.16.0.1"
!
ip dhcp pool Phone_0
 host 172.16.3.0 255.255.252.0
 hardware-address 0004.f200.0000
!
ip dhcp pool Phone_1
 host 172.16.3.1 255.255.252.0
 hardware-address 0005.f600.0000
 option 66 ascii "172.16.0.3"

You would just keep assigning host reservations from there. The options in each host pool will only apply to that specific device. If no options are defined (as in Phone_0), the options from the parent pool will be inherited. Of course, in the latter case, you don't need to define a reservation for the phone at all, but it illustrates how things work.

[mohammed asif suleman]

As Jody Said, It is quite difficult using router based dhcp server,i didn't tried with multiple pools

here you can bind multiple devices in a single pool, you can try multiple pools, hope this works for you

ip dhcp pool ccp-pool
import all
origin file tftp://192.168.5.65/dhcp-bind-file.txt
domain-name my-domainname.com
option 150 ip 192.168.1.19 192.168.1.18 (tftp servers)
default-router 192.168.5.65     (router IP)
dns-server 192.168.1.25 192.168.12.26

#####Copy the file to router flash from any server#####
copy tftp flash 
192.168.1.101 
dhcp-bind-file.txt

The following is a sample static mapping text file:

name it as dhcp-bind-file.txt 
-------------------------------------------------------------------------------
*time* Jan 24 2014 10:33 PM
*version* 1
!IP address         Type    Hardware address     Lease expiration
192.168.5.66 /29   id      01f8.bc12.7a68.bc       Infinite
192.168.5.67 /29   id      01f8.bc12.7ab3.d0       Infinite
192.168.5.68 /29   id      01f8.bc12.8ed3.2d       Infinite
*end*
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