- #Cisco ios xe cannot add ip nat inside source route map how to#
- #Cisco ios xe cannot add ip nat inside source route map serial#
With this, your inside PCs could access the Internet using dynamic NAT (i.e., NAT overload or PAT). In addition to configuring static NAT, you may want to use dynamic NAT at the same time. The Web server would receive that request and respond back through the router, which would translate it back to the global IP address. So when users enter in their Web browser, the browser would translate it to 63.63.63.2, and the router would then translate it to 10.1.1.2. We also need to register the IP address of the mail and Web server in the global Internet DNS registry. You can even use this command if you have a dynamic DHCP IP address from your ISP on the outside of your router.
#Cisco ios xe cannot add ip nat inside source route map serial#
Router (config)# ip nat inside source static tcp 10.1.1.2 25 interface serial 0/0 25 If you don't, you can use the outside IP address on your router (Serial 0/0 in our case), and you could configure it like this: This configuration assumes you have a block of IP addresses. I chose port 25 for SMTP (sending mail), port 443 for HTTPS (secure Web), port 80 for HTTP (Web traffic), and port 110 for POP3 (receiving mail from the mail server when out on the Internet). We used the above port numbers because they fit the description of what we wanted to do, but keep in mind that your port numbers may be different.
Here's the missing link between the outside and inside NAT configurations: We need the NAT translations to translate the outside IP address of the Web/mail server from 63.63.63.2 to 10.1.1.2 (and from 10.1.1.2 to 63.63.63.2).
For our example, let's say we start out with this basic configuration: Now that we've covered the background info, let's get started with configuring static NAT. So, you need to write ACLs with the public IP addresses in mind. In other words, what happens first - NAT translation or firewall filtering? For example, when using ACLs, a check of the input ACL occurs before NAT translation. Whether you're using basic access control lists (ACLs) or the Cisco IOS firewall feature set, make sure you understand the Cisco IOS order of operations to configure your firewall for the right IP addresses (public or private). However, make sure that whatever you're using for your firewall also allows this traffic in. In this post, I'll provide the basic static NAT configuration. There are two important steps to get this traffic inside your network and to your Web/mail server:
It's a good idea to gather the data you'll need before you start. However, on a Cisco router using the command-line interface (CLI), you'll struggle if you don't know the proper commands or where to apply them. On a Linksys router with a basic Web interface, this isn't very hard to do. Here's our goal: We want to configure a static IP translation through the router from the outside (i.e., Internet) network to the inside (i.e., private) network. Figure A offers a diagram to help visualize the network. To start off, let's get a better idea of what we're working with. (For more information, see " Set up NAT using the Cisco IOS" and " Set up Port Address Translation (PAT) in the Cisco IOS.") Most of us use a form of NAT called Port Address Translation (PAT), which Cisco refers to as NAT overload. NAT transforms private IP addresses to public IP address so users can access the public Internet. Most people use NAT to connect to the Internet these days. This requires configuring a static NAT translation between the dedicated public IP address and the dedicated private IP address.
#Cisco ios xe cannot add ip nat inside source route map how to#
Someone recently asked me how to configure Network Address Translation (NAT) so that computers on the Internet could access his internal Web and mail server through his Cisco router.