/etc/passwd is a text file that stores user account information which is required during login. It gives useful information like user ID, group ID, home directory, shell, etc.
The /etc/passwd contains one line for each user. All fields are separated by a colon (:) symbol. Total seven fields as follows.
- Username: It is used when user logs in. It should be between 1 and 32 characters in length.
- Password: An x character indicates that encrypted password.
- User ID (UID): Each user must be assigned a user ID (UID). UID 0 (zero) for root and UIDs 1-99 are for other accounts. UID 100-999 are used by system for administrative purposes.
- Group ID (GID): The primary group ID
- User ID Info: The comment field. It allow you to add extra information about the users such as user’s full name, phone number etc. This field use by finger command.
- Home directory: Path to the directory the user will be in when they log in.
- Command/shell: Path of a command or shell (/bin/bash).
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