Use:useradd command in linux is used to add a new user in the system. In other words, it creates a new login account for a different user. But, only the root user can user useradd command in linux. Show
Syntax:useradd [options] [LOGIN] Example: Explanation: useradd command creates a new user with the name David. To verify the creation of the new user, check the contents of the passwd file, which is in the /etc directory. The last line shows the entry for the user David. This file contains the list of all the users in the system. Each user entry has seven fields to it. Name: the name of the user (e.g. David) Password: marked with x. Not visible UID: the user ID GID: the ID of the group to which the user belongs GECOS: Full user name User Home Directory: the home directory of the user to manage his files Default Shell: the shell used by the user for interaction useradd command by default assigns UID, GID, Home directory and default shell to a new user. Note: If you create a user, as shown above, you are required to set a password using the passwd command before you login. If you don’t do it and try to login, the system prompts for a password as shown below. Using Options with useradd commanduseradd command in linux can be used with various options. Some of the most common ones are: 1. Adding a comment/GECOS value-c : option assigns the value of GECOS field. For example: Here the new user Steve is assigned the GECOS value as Steve Smith which is the full name of the user. 2. Set Home Directory-d : option creates a home directory with a name and path of your choice. By default the home directory is created in /home directory with the same name as the user’s name. But with –d option you can create a home directory of your choice. For example: 3. Set UID of choice-u : option assigns a user ID of your choice. For example: Thus, the user David is given the UID 5555. 4. Assign a GID of choice-g : option assigns the user to an existing group rather than creating a new group for it. For example: Thus, the user David is assigned to the group with GID 1007 which is an existing group. Steve is already a member of 1007. 5. Adding User to Supplementary Groups-G : option adds the user to supplementary groups i.e. other groups to which a user might belong. For example, let’s consider that David’s primary group is Mac and now he joins two other projects – Linux and Windows. Now, the supplementary groups for David are – Linux and Windows. Mac is the primary group specified by “-g” while Windows and Linux are the supplementary groups specified by the “-G” option. The lid command shows that the user David belongs to three groups. A look at the /etc/group file shows that Linux and Windows are the supplementary groups for David. When invoked without the -D option, and with appropriate privilege, useradd creates a new user account using the values specified on the command line and the default values from the system. The new user account will be entered into the system files as needed, the home directory will be created, and initial files copied, depending on the command line options. When invoked with the -D option, useradd will either display the current default values, or, with appropriate privilege, update the default values from the command line. If no options are specified, useradd displays the current default values. The useradd command is a system administration utility, see Path For System Administration Utilities. Standard Options-c commentspecifies the new user's password file comment field value. -d home_dircreates the new user using home_dir as the value for the user's login directory. The default is to append the login name to default_home and use that as the login directory name. -g initial_groupspecifies the group name or number of the user's initial login group. The group name shall exist. A group number shall refer to an already existing group. If -g is not specified, the implementation will follow the normal user default for that system. This may create a new group or choose a default group that normal users are placed in. Applications which require control of the groups into which a user is placed should specify -g. -G group[,...]specifies a list of supplementary groups which the user is also a member of. Each group is separated from the next by a comma, with no intervening whitespace. The groups are subject to the same restrictions as the group given with the -g option. The default is for the user to belong only to the initial group. -m [-k skeleton_dir]specifies the user's home directory will be created if it does not exist. The files contained in skeleton_dir will be copied to the home directory if the -k option is used, otherwise the files contained in /etc/skel will be used instead. Any directories contained in skeleton_dir or /etc/skel will be created in the user's home directory as well. The -k option is only valid in conjunction with the -m option. The default is to not create the directory and to not copy any files. -p passwdis the encrypted password, as returned by crypt(). The default is to disable the account. -rcreates a system account, that is, a user with a User ID in the range reserved for system account users. If there is not a User ID free in the reserved range the command will fail. -s shellspecifies the name of the user's login shell. The default is to leave this field blank, which causes the system to select the default login shell. -u uid [-o]specifies the numerical value of the user's ID. This value shall be unique, unless the -o option is used. The value shall be non-negative. The default is the smallest ID value greater than 499 which is not yet used. Change Default Options-b default_homespecifies the initial path prefix for a new user's home directory. The user's name will be affixed to the end of default_home to create the new directory name if the -d option is not used when creating a new account. -g default_groupspecifies the group name or ID for a new user's initial group. The named group shall exist, and a numerical group ID shall have an existing entry. -s default_shellspecifies the name of the new user's login shell. The named program will be used for all future new user accounts. -c commentspecifies the new user's password file comment field value. Application UsageThe -D option will typically be used by system administration packages. Most applications should not change defaults which will affect other applications and users. Will useradd command create the user's home directory?The command -d sets home directory for the user (if it's different than the default which is /home/”user's name”). Using -d on its own will only set the home directory for the user, but does not create it.
What is the use of useradd command?The useradd command creates a new user account. The login parameter must be a unique string (its length is can be configured by administrators using the chdev command). You cannot use the ALL or default keywords in the user name. The useradd command does not create password information for a user.
What is default path of user home directory in Linux?In this tutorial, we're going to see how to change the default home directory of a user on Linux. By default, it's /home/{username}.
What is the default location where adduser creates new user home directory?Creating a User with Specific Home Directory
By default useradd creates the user's home directory in /home . If you want to create the user's home directory in other location, use the d ( --home ) option.
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