Overview
The Intelligent Resilient Framework (IRF) technology virtualizes multiple physical devices at the same layer into one virtual fabric to provide data center class availability and scalability. IRF virtualization technology offers processing power, interaction, unified management, and uninterrupted maintenance of multiple devices.
Figure 1 shows an IRF fabric that has two devices, which appear as a single node to the upper-layer and lower-layer devices.
Figure 1: IRF application scenario
IRF provides the following benefits:
Simplified topology and easy management—An IRF fabric appears as one node and is accessible at a single IP address on the network. You can use this IP address to log in at any member device to manage all the members of the IRF fabric. In addition, you do not need to run the spanning tree feature among the IRF members.
1:N redundancy—In an IRF fabric, one member acts as the master to manage and control the entire IRF fabric. All the other members process services while backing up the master. When the master fails, all the other member devices elect a new master from among them to take over without interrupting services.
IRF link aggregation—You can assign several physical links between neighboring members to their IRF ports to create a load-balanced aggregate IRF connection with redundancy.
Multichassis link aggregation—You can use the Ethernet link aggregation feature to aggregate the physical links between the IRF fabric and its upstream or downstream devices across the IRF members.
Network scalability and resiliency—Processing capacity of an IRF fabric equals the total processing capacities of all the members. You can increase ports, network bandwidth, and processing capacity of an IRF fabric simply by adding member devices without changing the network topology.
As shown in Figure 2, Device A and Device B form a two-chassis IRF fabric. The fabric has four MPUs (one active and three standbys), and two times the number of interface modules that a single device provides. The IRF fabric manages the physical and software resources of Device A and Device B in a centralized manner.
Figure 2: Two-chassis IRF fabric implementation schematic diagram
