[cisco-voip] DHCP not really working

Kelemen Zoltan keli at carocomp.ro
Fri Aug 17 13:28:03 EDT 2007


Hi!

It's a bit off-topic, however I'm all clueless, so any help would be 
appreciated.

I have a CCME (2811, with 12.4(13r)T), with 7911G phones installed. Two 
VLANs, one for data, one for voice.

The router should be responsible for DHCP for the phones, but it does 
not seem to work - phones already in the network have their IP adress, 
keep their address through a reset, but new phones added to the network 
can't get an IP.

However, more people have access to the router and it is very possible 
it might have been misconfigured.

For starters, I noticed a

no service dhcp

in the running config, so I removed that. The dhcp debug messages began 
to appear, but it seems like the router still can't find "itself":

Aug 17 14:13:41.160: DHCPD: DHCPREQUEST received from client 
0100.1bd4.60b5.e2.
Aug 17 14:13:41.160: DHCPD: Finding a relay for client 0100.1bd4.60b5.e2 
on interface FastEthernet0/1.2.
Aug 17 14:13:41.880: DHCPD: DHCPREQUEST received from client 
0100.1bd4.609c.cf.
Aug 17 14:13:41.880: DHCPD: Finding a relay for client 0100.1bd4.609c.cf 
on interface FastEthernet0/1.2.

Here are relevant parts of the configuration:

no ip dhcp use vrf connected
ip dhcp excluded-address 192.168.42.1 192.168.42.2
!
ip dhcp pool ITS
   network 192.168.42.0 255.255.255.0
   option 150 ip 192.168.42.1
   default-router 192.168.42.1
!
!
no ip domain lookup

......................

any ideas? useful show commands?
most sh ip dhcp ... commands show nothing, except for

Router#sh ip dhcp server statistics
Memory usage         23512
Address pools        1
Database agents      0
Automatic bindings   0
Manual bindings      0
Expired bindings     0
Malformed messages   0
Secure arp entries   0

Message              Received
BOOTREQUEST          0
DHCPDISCOVER         0
DHCPREQUEST          1912
DHCPDECLINE          0
DHCPRELEASE          0
DHCPINFORM           0

Message              Sent
BOOTREPLY            0
DHCPOFFER            0
DHCPACK              0
DHCPNAK              0

Router#sh ip dhcp pool ITS         

Pool ITS :
 Utilization mark (high/low)    : 100 / 0
 Subnet size (first/next)       : 0 / 0
 Total addresses                : 254
 Leased addresses               : 0
 Pending event                  : none
 1 subnet is currently in the pool :
 Current index        IP address range                    Leased addresses
 192.168.42.1         192.168.42.1     - 192.168.42.254    0

Thanks,
  Zoltan


More information about the cisco-voip mailing list