Most Common Mistakes in Redis

Most Common Mistakes in Redis

Redis, one of the most widely used databases for many years, is generally used as an auxiliary database and a caching layer and can perform operational operations very quickly by keeping the data in memory. In this way, it reduces the main database load and provides high efficiency by increasing application performance. With the widespread use of Redis, the most common mistakes are as follows:


  • Swap Usage

A Swap area on the disc is used in Linux operating systems when the Memory (RAM) is complete. Therefore, in this case, operations on the disc greatly slow the application. Since the use of Swap will significantly reduce the performance of Redis, it is recommended to turn off the Swap feature completely.


  • Choosing the Wrong Method for Persistent Data

In Redis, there are methods to keep the data on a disc, such as RDB and AOF to make the data kept in memory permanent. It is essential to choose the suitable method when it is desired to keep the data on the disc in case of system failures such as server crashes. For example, the RDB method can be selected where data should be backed up at specific intervals; the AOF method can be selected in cases where data is essential. It should not be lost, and no method can be used in cases where data is unimportant. In all these cases, it is essential to make the correct configuration.


  • Security Vulnerabilities

Redis does not provide authentication or access controls by default. However, if access permissions to the Redis server are not configured correctly, security vulnerabilities such as unauthorized access or data leakage can occur. Configuring Redis securely is essential, using authentication, and implementing network-level access controls where necessary.


Some Possible Security Vulnerabilities:

  • Incorrect configuration: By default, Redis can be set to be connected to the local network and not require authentication. In case of misconfiguration, Redis can be accessed without access control and may become vulnerable to unauthorized access.
  • Outdated versions: Older versions of Redis may have significant security vulnerabilities. Therefore, keeping Redis updated and applying the latest patches regularly is essential. With updates, known security vulnerabilities are fixed, and Redis performance vulnerabilities are fixed, making systems more stable.
  • Data injection: Redis accepts user input to process commands and data structure. If the input is not sufficiently validated or filtered, it can lead to data injection attacks (e.g., sending malicious commands).
  • Storing sensitive data on disc: Because Redis is an in-memory data store, this means that if someone accesses your Redis server, they can see any sensitive data you have stored. It is best practice not to store sensitive data such as passwords or credit card numbers on Redis to avoid this risk. Instead, vault applications such as Hashicorp Vault encrypt sensitive data are recommended.


  • Configuration Errors

There are a few essential details to be considered during configuration in Redis:

a ) Write Permission Error: The data directory or log file required for Redis to work properly must be writable. Redis may not work or generate errors if the relevant file does not have written permission.

b ) Port Error: The Redis server listens on port 6379 by default. If this port number is configured incorrectly or another application is using this port, Redis will not work by generating an error.

c ) Excessive B memory usage: As the data in Redis increases, the amount of memory used increases. If we do not limit this increase, it uses the memory the operating system will use and prevents it from running. For this, it is necessary to make a change by giving a suitable value to the "max memory" parameter in the Redis configuration file.