I am using an older Cisco 892 at our client's. I must use ppp to set up communication - so my primary interface is Dialer0. The config is getting IP from IPCP (ip address negotiated) and is getting a static address, x.x.x.97/32. I have another IP routed to this interface from the provider, x.x.x.96/32. (x.x.x is the same for both).
I need to have the traffic from my network routed to the primary address (.97), and I have a mail server which should use the secondary address.
If I configure
ip nat inside source static 10.1.10.15 x.x.x.96
everything works fine and this server is presenting itself to the outside world with .96.
Now I need to break things up and map certain ports to this server, certain ports to another server (implementing a new mail server and I need port 443, for starters, to point to another server). Hence, I do
ip nat inside source route-map NAT-INTERNET-BACKUP interface Dialer0 overload ip nat inside source static tcp 10.1.10.15 22 x.x.x.96 22 extendable
ip nat inside source static tcp 10.1.10.15 25 x.x.x.96 25 extendable
ip nat inside source static tcp 10.1.10.15 110 x.x.x.96 110 extendable
ip nat inside source static tcp 10.1.10.15 143 x.x.x.96 143 extendable
ip nat inside source static tcp 10.1.10.66 443 x.x.x.96 443 extendable
ip nat inside source static tcp 10.1.10.15 465 x.x.x.96 465 extendable
ip nat inside source static tcp 10.1.10.15 993 x.x.x.96 993 extendable
ip nat inside source static tcp 10.1.10.24 53 x.x.x.97 53 extendable
ip nat inside source static tcp 172.29.127.100 80 x.x.x.97 80 extendable
ip nat inside source static tcp 172.29.127.100 443 x.x.x.97 443 extendable
ip route 0.0.0.0 0.0.0.0 Dialer0 50
and
route-map NAT-INTERNET-BACKUP permit 10
match ip address 100
match interface Dialer0
Now, the traffic from both .15 and .66 is presented to the outside world as coming from .97. Inbound traffic to .96 is still flowing OK though, no problems there.
How do I persuade the thing to use outside IP .96 for inside IPs .15 and .66?
I have somehow come to:
no ip nat inside source route-map NAT-INTERNET-BACKUP interface Dialer0 overload
ip access-list extended SUBNET_NAT
deny ip host 10.1.10.66 any
permit ip 10.1.0.0 0.0.255.255 any
ip access-list extended HOST_NAT
permit ip host 10.1.10.66 any
route-map HOST_POOL permit 10
match ip address HOST_NAT
match interface Dialer0
route-map NAT_OVRLD permit 10
match ip address SUBNET_MAP
match interface Dialer0
ip nat pool mypool x.x.x.96 x.x.x.97 prefix-length 32
ip nat inside source route-map HOST_POOL pool mypool overload
ip nat inside source route-map NAT_OVRLD interface Dialer0
What I'm struggling with is the definition of pool (both addresses are /32) and the question whether this will work at all and where to use my existing access-list 100.
Anybody able to offer some help to a Cisco noob? ;)
