What is the primary function of HSRP/VRRP in a network gateway configuration?

• A. They provide gateway failover using a shared virtual IP.
• B. They configure routing protocols like OSPF.
• C. They enforce firewall rules.
• D. They manage DNS.

Answer: (A)

Providing uninterrupted default gateway is the main purpose. HSRP and VRRP create a single shared virtual IP address that devices on the local network use as their gateway. One router is the active device and responds to ARP for that virtual IP, forwarding traffic toward its destination, while other routers stay in standby. If the active router fails or loses reachability, a standby router takes over the virtual IP and becomes the new active gateway, so hosts continue sending traffic without needing any network changes. This setup keeps gateway availability high and minimizes downtime.

They don’t configure routing protocols like OSPF, don’t enforce firewall rules, and don’t manage DNS. Their role is specifically to ensure there’s always a working gateway by providing a reliable, shared virtual IP.