What is HTTP session replication?
One of the key concerns of organizations is that their websites provide 100% availability and uptime. Interviewers will ask you questions like this to ensure that you know how to architect the website to achieve this goal. Since this functionality is critical to the organization, the interviewer will likely ask you follow-up questions about the topic and explore it in more detail. They may also ask related questions such as different approaches to achieving this goal and what features you can design into their website to ensure that it is always available.
As an experienced web architect, responding to this type of question should be no problem. However, if you're new to the profession and haven't used session replication in your previous roles, this may be a challenging question. Whenever you are unfamiliar with the topic or don't know the answer to an interviewer's question, the best response is to admit this and then describe how you would locate the information. Interviewers will appreciate your honesty.
"HTTP session replication is a process that creates a primary session state on the webserver. This is the first point the web user connects to. A second session state that is a replica of the first is then created on another server instance in the cluster. The replica is always kept up-to-date so that it may be used if the server that hosts the original instance fails. Both instances need to be in the same cluster for this to function properly."
