Memcached
Memcached is a high-performance, distributed memory object caching system. It is used to speed up dynamic web applications by reducing the database load. Memcached stores data in memory to provide faster access to frequently requested data.
What is Memcached
Memcached is an open-source, high-performance, distributed memory object caching system. It is designed to speed up dynamic web applications by alleviating database load. Memcached achieves this by storing data in memory, allowing for faster retrieval of frequently accessed data.
Originally developed by Brad Fitzpatrick for LiveJournal in 2003, Memcached has since become a popular caching solution used by many large-scale web applications. Its simplicity and effectiveness have made it a staple in the toolkit of web developers and system administrators.
Memcached operates by storing key-value pairs in memory, which can be quickly accessed by applications. This reduces the need to repeatedly query the database for the same data, significantly improving the performance and scalability of web applications. It is commonly used in conjunction with databases and other data stores to provide a seamless caching layer.
Companies like Facebook, Twitter, and Wikipedia use Memcached to handle large volumes of data and traffic. Its ability to distribute the cache across multiple servers ensures high availability and fault tolerance, making it a reliable choice for high-demand environments.
Security risk
If port 11211 is open and the Memcached service is running, it can be exploited by attackers to perform distributed denial-of-service (DDoS) attacks. Unauthorized access to the cache can also lead to data leakage, as sensitive information stored in memory could be exposed. It is crucial to secure this port and restrict access to trusted sources only.
In our UFW tutorial you can follow instructions how you can configure UFW to close port 11211. Use StackChanges to monitor if the Memcached port is closed and stays closed. StackChanges will send an alert if port 11211 is open again.