Hi,
I have the following config running on an 881 which is connection to an ISP via an external ADSL modem.
In it's current form, it is responding to any DNS request from any external IP address. I need to close this. I'm aware I can do this with an ACL but I'm not sure it should be responding in the first place. Can anyone see a problem with the config?
Current configuration : 2804 bytes
!
version 15.2
no service pad
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname jtg-rtr1
!
boot-start-marker
boot system flash:c880data-universalk9-mz.152-4.M2.bin
boot-end-marker
!
!
!
no aaa new-model
memory-size iomem 10
clock timezone GMT 0 0
clock summer-time BST recurring
!
!
!
!
!
ip dhcp excluded-address 172.16.1.1 172.16.1.99
!
ip dhcp pool mainPool
import all
network 172.16.1.0 255.255.255.0
default-router 172.16.1.1
dns-server 172.16.1.1
option 66 ascii 172.16.1.1
!
!
!
ip domain name router.local
ip name-server 8.8.8.8
ip name-server 8.8.4.4
ip cef
no ipv6 cef
!
!
!
!
ip ssh time-out 60
ip ssh authentication-retries 2
csdb tcp synwait-time 30
csdb tcp idle-time 3600
csdb tcp finwait-time 5
csdb tcp reassembly max-memory 1024
csdb tcp reassembly max-queue-length 16
csdb udp idle-time 30
csdb icmp idle-time 10
csdb session max-session 65535
!
!
!
!
!
!
interface FastEthernet0
no ip address
!
interface FastEthernet1
no ip address
!
interface FastEthernet2
no ip address
!
interface FastEthernet3
no ip address
!
interface FastEthernet4
description ADSL WAN Interface
no ip address
no ip redirects
no ip unreachables
no ip proxy-arp
ip nat outside
ip virtual-reassembly in
duplex auto
speed auto
pppoe enable group global
pppoe-client dial-pool-number 1
no cdp enable
!
interface Vlan1
ip address 172.16.1.1 255.255.255.0
ip nat inside
ip virtual-reassembly in
ip tcp adjust-mss 1440
no autostate
!
interface Dialer1
description ADSL WAN Dialler
ip address negotiated
no ip unreachables
ip nat outside
ip virtual-reassembly in
encapsulation ppp
dialer pool 1
ppp authentication chap pap callin
ppp chap hostname [isp username]
ppp chap password [isp password]
ppp ipcp route default
no cdp enable
!
ip forward-protocol nd
no ip http server
no ip http secure-server
!
ip dns server
ip nat inside source list 1 interface Dialer1 overload
!
access-list 1 permit 172.16.1.0 0.0.0.255
dialer-list 1 protocol ip permit
no cdp run
!
!
!
!
end
