Problems with ftp and "ip nat outside"

[carlos.navas]

Hello,

we have routers 1801 that connect with a central router7200 with tunnels.This central route all traffic from the rest network. The LAN for our 1801 is 10.255.x.x. We have a NAT for the case that we have other subnet that need access for our central net, and with this the router nat the ip to loopback ip.

Well, the problem is this:

When we have to do a ftp to ip 53.x.x.x from server in the 10.255.x.x all is ok. But if we include the line "ip nat outside" in the interfaz tunnel for 1801, the ftp fail. This is strange because this nat don?t run in this case because only work with the origin is diferent from 10.255.x.x.

Can any help for this? I atacch a configuration.

Very thanks

[a-vazquez]

The Cisco 1811 and Cisco 1812 integrated services fixed-configuration routers support Point-to-Point Protocol over Ethernet (PPPoE) clients and network address translation (NAT). Multiple PCs can be connected to the LAN behind the router. Before the traffic from these PCs is sent to the PPPoE session, it can be encrypted, filtered.

http://www.cisco.com/en/US/products/ps5853/products_configuration_guide_chapter09186a00804582b0.html