DHCP and NAT overload

[opnineopnine]

Hi all,

I have the following topology :

Router 3:
     DHCP and access to Internet

Switch

   Simple layer 2 with vlan 10

 Router 4:

    Gets ip from the DHCP but when I want to ping to the outside (8.8.8.8) i don't get any answer.

    If I ping the outside interface from the Router 3 I get an answer.

Thanks. 

[paul driver]

Hello

Rtr 3 interface connecting to the switch I am guessing is on a different subnet then it outside interface?

Rtr4 is acting as a host device, and as such that subnet it resides on needs to be natted to the outside world,

Please post you configuration and we can review

res

Paul

[opnineopnine]

Hello sir,

The R3 interface is:

DHCP#sh run int e0/1
Building configuration...

Current configuration : 120 bytes
!
interface Ethernet0/1
description Inside
no ip address
ip nat inside
ip nat enable
ip virtual-reassembly in
end

interface Ethernet0/1.10
encapsulation dot1Q 10
ip address 157.10.10.1 255.255.255.0
end

!

R4 will be a host but yes I have to nat it for the outside, the outside IP is 101.1.108.241

[Georg Pauwen]

Hello,

make sure your configs look like below:

Router_3

ip dhcp excluded-address 157.10.10.1
!
ip dhcp pool LAN
network 157.10.10.0 255.255.255.0
default-router 157.10.10.1
dns-server 8.8.8.8
!
interface Ethernet0/0
description outside
ip address 101.1.108.241
ip nat outside
!
interface Ethernet0/1
description Inside
no ip address
ip nat inside
ip virtual-reassembly in
!

interface Ethernet0/1.10
encapsulation dot1Q 10
ip address 157.10.10.1 255.255.255.0
ip nat inside
!
ip nat inside source list 1 interface Ethernet0/0 overload
!
access-list 1 permit 157.10.10.0 0.0.0.255

Switch

interface Ethernet0/0
switchport mode trunk
switchport trunk encapsulation dot1q
!
interface Ethernet0/1
switchpprt mode access
switchport access vlan 10

Router_4

interface Ethernet0/0
ip address dhcp

[paul driver]

Hello

Georg's config look okay  - just like to state RTR1 would also require a static default route towards RTR2

rtr 1
ip route 0.0.0.0 0.0.0.0 fa0/0 101.1.108.242

res

Paul