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Simple issue on NAT

Peppe C
Posts: n/a
I'm sorry for the silly issue, but I have a very basic knowledge of Cisco
and today I've lost many hours without seeing the light.
The configuration is very simple: I have a couple of 803 linked via ISDN
line named Rome and Naples.
In Rome my subnet is, in Naples is
Unfortunately I cant call the subnet from Rome because it's
already used in the WAN I'm connected.

So I have to use a static NAT to translate the only address I'm interested in

On the NAPLES router I've configured the BRI0 isdn port as inside and the
ethernet (where is connected the remote host) as outside.
When I ping from naples the IP is correctly converted in and everything goes fine.

00:03:06: IP: tableid=0, s= (local), d=
(Ethernet0), routed via RIB
00:03:06: IP: s= (local), d= (Ethernet0), len
100, sending
00:03:06: NAT: s=, d=> [11]
00:03:06: IP: tableid=0, s= (Ethernet0), d=
(Ethernet0), routed via RIB
00:03:06: IP: s= (Ethernet0), d= (Ethernet0), len
100, rcvd 3

When I ping from rome, the router dials and connects to naples, but ping
Debugging on Naples I see all this encapsulation errors and no NAT

00:04:22: %ISDN-6-CONNECT: Interface BRI0:1 is now connected to 061234567
00:04:23: IP: tableid=0, s= (Dialer1), d=
(Ethernet0), routed via RIB
00:04:23: IP: s= (Dialer1), d= (Ethernet0),
g=, len 100, forward
00:04:23: IP: s= (Dialer1), d= (Ethernet0), len
100, encapsulation failed

What can it be? I know its a missing route but I can't find it !!!
As you can see from the router the configuration is quite simple...
Could you be so kind to point me in the right direction?

Many thanks

version 12.3
hostname NAPLES
username ROME password 7 asdasdasdas
no aaa new-model
ip subnet-zero
no ip domain lookup
isdn switch-type basic-net3
interface Ethernet0
description connected to EthernetLAN_1
ip address
ip nat outside
no keepalive
interface BRI0
description connected to ROME
no ip address
ip nat inside
encapsulation ppp
dialer rotary-group 1
dialer-group 1
isdn switch-type basic-net3
no cdp enable
interface Dialer1
description connected to ROME
ip unnumbered Ethernet0
encapsulation ppp
no ip split-horizon
dialer in-band
dialer map ip name ROME broadcast 01234567
dialer hold-queue 10
dialer-group 1
no cdp enable
ppp authentication chap
ip nat outside source static
ip route Ethernet0
ip classless
no ip http server
dialer-list 1 protocol ip permit
snmp-server engineID local 00000009020001308003F817
snmp-server community public RO

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