VRF

Virtual Routing and Forwarding, or VRF is a technology used in networking that allows multiple instances of a routing table to coexist within the same router at the same time. This enables the partitioning of a network into multiple virtual networks, each with its own set of routing policies and rules, essentially segmenting the network for specific purposes, users, or functions without requiring multiple physical routers.

VRFs are like VLANs for routers, instead of using a single global routing table we can use multiple virtual routing tables. Each interface of the router is assigned to a different VRF.

In a router that supports VRF, each virtual routing and forwarding instance operates as if it were a separate router, with its own set of interfaces, routing protocols, and forwarding tables. Traffic routing decisions are made independently within each VRF, based on its specific routing table. VRF is widely used in multi-tenant environments, enterprise networks, and by ISPs to create distinct virtual networks that cater to different customers or operational requirements.

VRFs are also used extensively in combination with other technologies such as MPLS, MP-BGP and others.

Links:

https://networklessons.com/mpls/vrf-lite-configuration-on-cisco-ios