Content switching is the process of directing client traffic based on the data payload being transferred, aside from common factors such as source, destination, or IP addresses. In the context of content switching, routing decisions are also based on HTTP header contents, URL parameters, and other application-specific information.
How does content switching work?
We've touched on various pieces of information that impact content switching, but to grab this data, content switches must be protocol-aware. By being HTTP-friendly, content switches work at Layer 7 (OSI model) to intelligently distribute requests among multiple servers. This boosts the scalability, performance, and reliability of applications through resource optimization.
Content switching is also common within load balancers and application delivery controllers (ADCs). It allows administrators to set up content-based routing policies, enables global server load balancing (GSLB), and even SSL/TLS termination. Content switches can even redirect clients away from a failed server to another working server that hosts the same resources. This promotes high availability and stops users from receiving error codes while accessing services.
Does HAProxy offer content switching?
Yes! HAProxy supports content switching as a primary load-balancing feature. As we've described above, HAProxy can distribute requests to specific servers based on their contents.
You can choose which backend to route HTTP requests to. HAProxy can even match samples from current traffic and match them against patterns. Content switching is also handy when applications have unique settings pertaining to hosting, HTTP traffic categorization, resource allocations, health checks, timeouts, and more.
