Unit 1: Network Infrastructure
This will allow you to demonstrate your networking skills, knowledge, and abilities, with a focus on enterprise-level switching, routing, and multicast components that support cross-platform (inter)operability and integration with the most recent software-defined technologies.
The Virtual Routing and Forwarding is referred to as a VRF. It is a method for creating several routing tables and ensuring that they are completely and completely distinct from one another, as well as from the global routing table that is stored on the router. Although a VRF may contain a large number of interfaces, an interface can only be associated with a single VRF. Each interface can then be connected to exactly one VRF (or the global routing table).The setting is simple:
R1(config)# ip vrf red
R1(config-vrf)# rd 1:1
R1(config)# ip vrf blue
R1(config-vrf)# rd 1:2
R1(config)# interface GigabitEthernet0/1
R1(config-if)# ip vrf forwarding red
R1(config-if)# ip address 192.168.1.1 255.255.255.0
R1(config-if)# exit
R1(config)# interface GigabitEthernet0/2
R1(config-if)# ip vrf forwarding blue
R1(config-if)# ip address 192.168.2.1 255.255.255.0
R1(config-if)# exit
When you assign an interface to a VRF, any IP address that was already set up on that interface is erased so that the new routing table doesn’t have any duplicate addresses. VRFs can only be used on Layer 3 connections, which makes sense.
By correctly mapping VRFs to the links linking two routers, you can extend VRFs beyond a single router. This produces VRF Lite, the most fundamental method of creating VPNs, which involves running VPNs in parallel across numerous devices. Since each VPN requires its own dedicated inter-router link, this method isn’t highly scalable, but it is the simplest approach to create non-overlapping VPNs in a network. So, if you have two routers and one hundred virtual private networks (VPNs), you’ll need to allocate one hundred connections between the two routers. The link could be an independent interface or methods like Ethernet VLAN or Frame-Relay PVC.
