[FW1] Natting two 10.0.0.0 networks

["Varnam, Gary" <Gary.Varnam@FW1-NOSPAMsalford.gov.uk>]

Hello,
One of our partners who wants connect router to router but they run there
network based on the 10.0.0.0 network as we do so some NATTing will have top
occur.
They cannot perform any NAT translation. What I propose is all packets from
the external interface from network 10.30.33.0 be translated to 172.21.21.0
and vice Vera.
I have two objects up 
Contractor_Original with ip address 10.30.33.0 mask 255.255.255.0 and
Contractor_NAT with ip address 172.21.21.0 mask 255.255.255.0
In the rule base I have allowed both objects to telnet to host, on the NAT
Rules I have said 
Source of Contractor_Original change to Contractor_NAT 
destination of Contractor_NAT change to Contractor_Original.
The packet is accepted by the firewall but NAT does not occur. 
On the firewall I have a route 10.0.0.0 with mask 255.0.0.0 via Internal
interface and 10.30.33.0 with mask of 255.255.255.0 via external interface.
local.arp is empty.
Any ideas?
 

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Hello,

One of our partners who wants connect router to router but they run there network based on the 10.0.0.0 network as we do so some NATTing will have top occur.

They cannot perform any NAT translation. What I propose is all packets from the external interface from network 10.30.33.0 be translated to 172.21.21.0 and vice Vera.

I have two objects up

Contractor_Original with ip address 10.30.33.0 mask 255.255.255.0 and

Contractor_NAT with ip address 172.21.21.0 mask 255.255.255.0

In the rule base I have allowed both objects to telnet to host, on the NAT Rules I have said

Source of Contractor_Original change to Contractor_NAT

destination of Contractor_NAT change to Contractor_Original.

The packet is accepted by the firewall but NAT does not occur.

On the firewall I have a route 10.0.0.0 with mask 255.0.0.0 via Internal interface and 10.30.33.0 with mask of 255.255.255.0 via external interface.

local.arp is empty.

Any ideas?