Main functions of HSRP in the backup router

For many enterprises, the optimization of the network environment is very important, so the role of the backup router is very important at this time. The high reliability of network systems has increasingly become one of the key factors in the design of the entire system. enterprises and consumers rely on Intranet or Internet services for key business communications.

To ensure that their networks and applications can run at normal times, Cisco's Hot backup routing Protocol HSRP Hot Standby Router Protocol can meet customer needs and provide network redundancy, in today's large networks, network disconnection is not allowed. Most companies now use the backup router function to achieve this purpose, HSRP is a popular Default Gateway Protocol and is widely used in Cisco multi-layer switching networks.

Features of HSRP:

In the HSRP group, only the active backup router forwards data packets to the vro. The vro with the highest backup priority in the group becomes active. If the active router fails, the backup router automatically functions as an active router. The routers in the HSRP Group communicate with each other through UDP-Based Multi-Point broadcast hello data packets. To a certain extent, load balancing can be achieved through multiple HSRP groups.

HSRP backup group member

Active router: forwards data packets sent to the virtual router.
Backup vro: monitors the running status of the HSRP group. When the active vro cannot run, it quickly assumes the responsibility for packet forwarding.
Vro: represents a continuous working vro to the end user.

Today, I will simply configure the router so that it can provide services to the client at all times. Activities and backup routers are generated by election and are selected based on the backup router priority (high value ), active Routers simulate virtual routers. The active router is responsible for receiving and processing the traffic sent from the terminal to the virtual router.

The active router regularly sends Hello messages to the Ethernet to tell other routers that I am an active router. My priority, Hello interval, Hold interval, and IP address of the virtual router and the active router. The backup router monitors and detects the status of the active router. The backup router also regularly notifies the vro on the network (the same as the active router ). When the active or backup router fails, the vro is always available. When the active vro fails and the backup vrohello fails to receive the active vrohello Hello within the Hold interval, it will think that the active vro is faulty and then upgrade itself to the active vro.