FHRP
First Hop Redundancy Protocol is a redundancy protocol for the default gateway. Say you have a simple network as follows: In this network, you have a default gateway of 10.1.1.1 on your server(10.1.1.10). What if 10.1.1.1 goes down? The network experience of your server's user is impacted and there needs to be a manual change to 10.1.1.2. FHRP technologies help us alleviate this issue by letting the 2 routers work in High Availability mode. There are 2 Cisco proprietary FHRP technologies: 1) HSRP - Hot Standby Routing Protocol 2) GLBP - Gateway Load Balancing Protocol Open source: 3) VRRP - Virtual Router Redundancy Protocol With all of the three technologies, you setup a virtual IP, e.g. 10.1.1.3 on both the routers and let the two routers know that they are in a group with the third IP, this way if one of the routers go down, the other takes up the default gateway job and the network in not impacted. --- Cisco commands to setup HSRP on a Cisco sw...