Definition: '.0991_user_9hcldb.conf' refers to a configuration file, often used in Linux systems for managing user authentication information. This file primarily serves as a means for securely storing user data in a Unix/Linux environment. It contains crucial details like usernames and passwords for various users, which are then stored across multiple servers using SSH or another secure connection method. The definition of ''.0991_user_9hcldb.conf' is that it is an important configuration file used for authentication purposes within Linux systems.
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