WINDOWS SERVER 2012R2 ROUTING ONLY

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COURSE: 70-411
SECTION: Configure Network services and Access
OBJECTIVE: Routing ONLY

Suppose that the public facing network adapter is assigned to a private IP address, e.g., 192.168.0.1, on the subnet 192.168.0.0/24, instead of 137.107.0.1. Is it possible to ping from DC to an public IP address,.e.g, 216.58.194.206 (which is IP address of the google.com), given that NAT is not configured on this scenario. When I tried this, I could ping from DC to any machine that belong to 192.168.0.0/24 subnet but not any public IP address. What is wrong here? I checked the routing table on EDGE machine, and it showed as follows:

My physical host machine uses 192.168.0.1 as a default gateway to access Internet. From the screenshot above on Persistence Routes, I thought the second entry would route packet from any network, including pubic network, to default gateway which can route the packet to destined public IP address, Would you please clarify the what Persistent Routes exactly is doing here?

Also I am wondering how you can assign a network adapter interface to an public IP address. Given that I have a modem and a router, should I disable NAT feature on both modem and router so that ISP would directly assign one of my network adapter interface of the EDGE machine to an public IP address?

Thank you for your instruction,

@Truong-Hoang61 said in WINDOWS SERVER 2012R2 ROUTING ONLY:

COURSE: 70-411
SECTION: Configure Network services and Access
OBJECTIVE: Routing ONLY

Suppose that the public facing network adapter is assigned to a private IP address, e.g., 192.168.0.1, on the subnet 192.168.0.0/24, instead of 137.107.0.1. Is it possible to ping from DC to an public IP address,.e.g, 216.58.194.206 (which is IP address of the google.com), given that NAT is not configured on this scenario. When I tried this, I could ping from DC to any machine that belong to 192.168.0.0/24 subnet but not any public IP address. What is wrong here? I checked the routing table on EDGE machine, and it showed as follows:

Private IP Addresses (RFC 1918) are not allowed to communicate on Internet directly. Hence, why we use NAT on our routers. This allows the Private IP (192.168.0.1) to be translated into the public IP addresses assigned by our ISP. If we ping, the router translates to the public IP and the destination address is responding back to the Public IP of the router doing NAT. NAT on the router is translating it back to the private IP address on our LAN. To put a Private IP address on the public facing interface will not allow it communicate to public IP addresses on the internet.

My physical host machine uses 192.168.0.1 as a default gateway to access Internet. From the screenshot above on Persistence Routes, I thought the second entry would route packet from any network, including pubic network, to default gateway which can route the packet to destined public IP address, Would you please clarify the what Persistent Routes exactly is doing here?

The routing table is showing (from left to right) If packets were sent to the the "Network Address" it would be sent to the interface with that IP address.

Also I am wondering how you can assign a network adapter interface to an public IP address. Given that I have a modem and a router, should I disable NAT feature on both modem and router so that ISP would directly assign one of my network adapter interface of the EDGE machine to an public IP address?

Normally, if you plug your PC directly into your Cable Modem, you should see your ISP's assigned address on that computer.

Thank you for your instruction,

Thanks Ronnie for the clear explanation, clarifying my point of confusion between ROUTING and NAT.

a.) If so, I can route a private IP address from DC to a public IP address, without NAT configured, as long as one of the network adapter interface of the Edge machine must be set to an ISP-assigned public IP address. Is my understanding correct?

b.) In the Routing Table from the Edge machine, the second entry shown as
0.0.0.0 0.0.0.0 192.168.0.1 means that the edge machine can route to any specific sub-net, without NAT configured, in the private network only. In another word, it is LAN routing not WAN routing. Am I right?

Correct my assumptions above if they are misunderstood.

Again, thank you, Ronnie, for your pertinent feedback that gave an insight into question in discussion.

@Truong-Hoang61 said in WINDOWS SERVER 2012R2 ROUTING ONLY:

Thanks Ronnie for the clear explanation, clarifying my point of confusion between ROUTING and NAT.

a.) If so, I can route a private IP address from DC to a public IP address, without NAT configured, as long as one of the network adapter interface of the Edge machine must be set to an ISP-assigned public IP address. Is my understanding correct?

No. You'll not be able to put a Private IP address on a public facing interface. The only way possible to route a private IP address to a public address is THROUGH NAT. RFC 1918 prevents traffic from Private IP addresses from getting to the Internet. Any ISP that violates that can and will be penalized somehow.

Usually, the address assigned by your ISP to your location is in one of two configurations:

1. To a Wireless Router
2. To a single PC
   If the first, then the Wireless Router will get a public IP Address and will implement NAT for your internal network.
   If the 2nd, then only that PC will access your internet connection.

b.) In the Routing Table from the Edge machine, the second entry shown as
0.0.0.0 0.0.0.0 192.168.0.1 means that the edge machine can route to any specific sub-net, without NAT configured, in the private network only. In another word, it is LAN routing not WAN routing. Am I right?

Without NAT, you will only route to other Private IP networks. The 0.0.0.0 0.0.0.0 192.168.0.1 is a default route, regardless of NAT or No NAT setup this means that if a packet arrives and matches any address besides the route above that one, means it's going to send out that interface too. Normally, if traffic matches this network it means it's trying to leave the current network so it's sending it outbound from your interface 192.168.0.1. It could be sending toward your WAN or to another LAN without going through your WAN so the route is not about whether or not NAT is or is not configured.

Yes, Sir. I am very very clear now. I liked your presented reply.

Thank you very much.