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cisco 881w and DHCP issue


I have a cisco 881W. My ISP give me two subnet and gateway for them (Fa4 IP address in my configuration). There are three subnet in my company

- two subnets within real IP addresses (a.a.a.x and b.b.b.x in my configuration below)

- one subnet eithin private IP addresses (c.c.c.x in my configuration below)

And DHCP for each. I made configuration on my cisco 881:

WAN port was gateway

LAN ports was separate on thee VLANs

So port Fa0 was insert to  VLAN1 (IP a.a.a.a), port Fa1 was insert to VLAN2 (IP b.b.b.b), port Fa2 was insert to VLAN3 (IP c.c.c.c)

Also I was creare three DHCP pools: pools for subnet a.a.a.a, b.b.b.b and c.c.c.c

But I have issue. When I connected any client into any ports from Fa0 to Fa2 it get rendom IP address from any three pools what I have. Another words if I connected client DHCP into port Fa0 I can will get not only address from pool for c.c.c.0 subnet but and for a.a.a.a subnet and for b.b.b.b subnet.

What me to do?

#sh run

Building configuration...

Current configuration : 3470 bytes


version 15.1

no service pad

service timestamps debug datetime msec

service timestamps log datetime msec

service password-encryption






enable secret ----


no aaa new-model

memory-size iomem 10

crypto pki token default removal timeout 0



ip source-route




ip dhcp excluded-address c.c.c.1 c.c.c.100


ip dhcp pool pool

network c.c.c.0

default-router c.c.c.12


ip dhcp pool telephone

network a.a.a.208

default-router a.a.a.209


ip dhcp pool telephone1

network b.b.b.112

default-router b.b.b.113


interface FastEthernet0

switchport access vlan 1

no ip address


interface FastEthernet1

switchport access vlan 2

no ip address


interface FastEthernet2

switchport access vlan 3

no ip address


interface FastEthernet3

no ip address


interface FastEthernet4

ip address <IP address>

ip nat outside

ip virtual-reassembly in

duplex auto

speed auto

crypto map oldshcool


interface wlan-ap0

description Service module interface to manage the embedded AP

ip address

arp timeout 0


interface Wlan-GigabitEthernet0

description Internal switch interface connecting to the embedded AP

switchport mode trunk

no ip address


interface Vlan1

ip address c.c.c.12

ip nat inside

ip virtual-reassembly in


interface Vlan2

ip address a.a.a.208


interface Vlan3

ip address b.b.b.112


ip forward-protocol nd

no ip http server

no ip http secure-server


ip nat inside source list 100 interface FastEthernet4 overload

ip route <IP address>


logging esm config

access-list 100 permit ip c.c.c.0 any



New Member

cisco 881w and DHCP issue

Found error in my post (original cisco configuration correct, I'm mistake only here)


interface Vlan2

ip address a.a.a.209


interface Vlan3

ip address b.b.b.113



cisco 881w and DHCP issue


could you post following outputs:

-sh vlan-sw br

-sh interface status

-sh ip dhcp bindings

- sh ip int br | i Vlan



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New Member

cisco 881w and DHCP issue

#sh vlan-sw br

VLAN Name                             Status    Ports

---- -------------------------------- --------- -------------------------------

1    default                          active    Fa0, Fa3

3    VLAN0002                         active    Fa1

4    VLAN0003                         active    Fa2

1002 fddi-default                     act/unsup

1003 token-ring-default               act/unsup

1004 fddinet-default                  act/unsup

1005 trnet-default                    act/unsup

#sh int status

Port    Name               Status       Vlan       Duplex Speed Type

Fa0                        connected    1          a-full   a-100 10/100BaseTX

Fa1                        connected    2          a-full   a-100 10/100BaseTX

Fa2                        connected    3          a-full   a-100 10/100BaseTX

Fa3                        notconnect   1            auto    auto 10/100BaseTX

Wl0     Internal switch in connected    trunk      a-full  a-1000 10/100BaseTX

#sh ip dhcp binding

Bindings from all pools not associated with VRF:

IP address          Client-ID/              Lease expiration        Type

                    Hardware address/

                    User name

c.c.c.101      0164.00f1.7776.c0       Dec 21 2011 07:15 PM    Automatic

c.c.c.102      0100.1676.0e18.5c       Dec 21 2011 07:15 AM    Automatic

c.c.c.104      0100.1676.d3c0.4c       Dec 21 2011 07:17 AM    Automatic

c.c.c.187      011c.6f65.49f6.8d       Dec 21 2011 07:49 AM    Automatic

b.b.b.117      0100.0e08.3a29.a3       Dec 21 2011 07:16 AM    Automatic

#sh ip int br | i vlan

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