Find the Server or Keep the Session?

About this interactive

Servers can be redundant, but the client connects to a service on one of them, by IP address. The lesson names two problems. Reaching a live server: when that server goes offline, how does the client know, and how does it find another server? A load balancer in front, a shared address that moves, or a DNS change can point the client somewhere that works. Keeping the session: a client builds up a session with one server, at the TCP level or in the application. Moved to another server, it can lose that in-session information unless the design keeps it, for example by storing sessions on the shared database behind the servers. Load balancing and clustering can each solve parts of both problems, which is why they overlap.

What you'll learn

Tell the two problems service redundancy has to solve, getting clients to a live server and keeping their session when they move, apart, along with the fixes for each

Aligned to

CompTIA Security+

3.4 Explain the importance of resilience and recovery in security architecture.

Key terms

Session Persistence: The ability to maintain a user's session data consistently across multiple servers in a load-balanced or clustered environment.
Load Balancer: A device or software that distributes incoming network traffic across multiple servers to ensure availability and performance.
Clustering: A configuration where multiple servers or nodes work together as a single logical system to provide high availability, load balancing, or both, so that service continues if one node fails.
Failover: The automatic switching to a redundant system or component when the primary one fails.

Topics

Interactive Streak Sort

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