The reasons for session failure include session timeout, session number limit, session integrity check, server restart, browser or device problems, etc. Detailed introduction: 1. Session timeout: The server sets a default timeout for the Session. When the user does not interact with the server for a period of time, the Session will automatically expire; 2. Session number limit: The server has a number of Sessions for each user. A limit is set. When the number of Sessions created by a user exceeds this limit, the latest one will overwrite the oldest one and so on.
The main reasons for Session failure are as follows:
Session timeout: The server sets a default value for Session The timeout period, when the user does not interact with the server for a period of time, the Session will automatically expire. This timeout can be achieved by setting the server's configuration file or code.
Session limit: The server sets a limit on the number of Sessions that each user can create. When the number of Sessions created by a user exceeds this limit, the latest Session will overwrite the earliest Session, causing the Session to become invalid.
Session integrity check: When the server creates a Session, it may perform authentication or other integrity checks on the user. If the user fails these checks, the server destroys the Session, causing the Session to become invalid.
Server restart: When the server is restarted, all Sessions in memory will be invalidated. Therefore, before the server is restarted, important Session data needs to be saved to persistent storage so that the Session can be restored after the server is restarted.
Browser or device issues: Sometimes, Session failure may be caused by browser or device issues. For example, the browser has disabled cookies, or the device's network connection is unstable.
In short, there are many reasons for Session failure, which need to be analyzed and troubleshooted according to the specific situation. In practical applications, session failures can be avoided or reduced by properly setting the session timeout, limiting the number of sessions, and performing integrity checks.
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