FHRP itself describes different Gateway Redundancy / Fault-Tolerant protocols, that allow for transparent gateway fail-over upon router failure, by using different methods of creating Virtual Router IPs for host gateways.

Cisco documentation describes FHRP as being either HSRP or VRRP, cited on their official website here, which I will cover along with GLBP – However there are other Redundancy protocols that are worth knowing exist on the Wikipedia page for FHRP located here.

These are note IP Routing protocols and do not influence routes / routing tables, these are used for Default Gateway fail-over and load-balancing methods, it will only effect the device in use as configured with the FHRP protocol being used.

HSRP / VRRP / GLBP are all very similar in operation with slight differences, so it is important to note the slight differences in operation / configuration of each, along with knowing that FHRP itself is not a protocol but rather describes a specific protocol in use!

With that I’ll get into HSRP on the next post and start the FHRP party train going! 🙂