Keepalived
Keepalived is an open-source software tool that provides high availability and load balancing for Linux-based systems, primarily using the Virtual Router Redundancy Protocol (VRRP) to manage failover between servers. It monitors the health of servers and automatically switches traffic to a backup server if the primary fails, ensuring service continuity. It is commonly used in web server clusters, database replication setups, and other critical infrastructure to prevent downtime.
Developers should learn and use Keepalived when building fault-tolerant systems that require high availability, such as web applications, databases, or network services where downtime is unacceptable. It is particularly useful in scenarios like load-balanced web server farms, where it can manage IP failover and health checks to maintain seamless user access. For example, in a production environment with multiple web servers, Keepalived ensures that if one server goes down, traffic is automatically redirected to a healthy backup without manual intervention.