In particular such a line should be after the %wheel line if your user is in this group.Įnable explicitly defined commands only for user USER_NAME on host HOST_NAME without password: Note: The most customized option should go at the end of the file, as the later lines overrides the previous ones. To allow members of group wheel sudo access: To allow a user to run all commands as any user but only on the machine with hostname HOST_NAME: To allow a user to gain full root privileges when they precede a command with sudo, add the following line: # Set default EDITOR to restricted version of nano, and do not allow visudo to use EDITOR/VISUAL.ĭefaults editor=/usr/bin/rnano, !env_editor To change the editor of choice permanently system-wide only for visudo, add the following to /etc/sudoers (assuming nano is your preferred editor): To change the editor permanently, see Environment variables#Per user. This might come in handy in case you want to circumvent locking the file with visudo. To establish nano as the visudo editor for the duration of the current shell session, export EDITOR=nano to use a different editor just once simply set the variable before calling visudo:Īlternatively you may edit a copy of the /etc/sudoers file and check it using visudo -c /copy/of/sudoers. The sudo package is compiled with -with-env-editor and honors the use of the SUDO_EDITOR, VISUAL and EDITOR variables. visudo(8) warns that configuring visudo to honor the user environment variables for their editor of choice may be a security hole, since it allows the user with visudo privileges to run arbitrary commands as root without logging simply by setting that variable to something else.Always edit it with visudo to prevent errors. It is imperative that sudoers be free of syntax errors! Any error makes sudo unusable.To use sudo, simply prefix a command and its arguments with sudo and a space: To begin using sudo as a non-privileged user, it must be properly configured. Sudo can also be used to run commands as other users additionally, sudo logs all commands and failed access attempts for security auditing. By enabling root privileges only when needed, sudo usage reduces the likelihood that a typo or a bug in an invoked command will ruin the system. Unlike su, which launches a root shell that allows all further commands root access, sudo instead grants temporary privilege elevation to a single command. Sudo is an alternative to su for running commands as root. However, in the case that the SHELL environment variable is set in the invoking user's environment (which it usually is, and it is typically /bin/bash), and that the target user has a login shell which differs from this (such as /usr/sbin/nologin), there is then a difference between which shell gets executed by these two commands, and this is what you are seeing.Sudo allows a system administrator to delegate authority to give certain users-or groups of users-the ability to run commands as root or another user while providing an audit trail of the commands and their arguments. So the two commands look similar (largely coincidentally) and have a somewhat similar effect when the target user has the same login shell as that of the invoking user. The su user command could be run without the use of sudo, but by running it as root it will not require the password of the target user. The su command will then invoke the login shell of the specified username. Sudo su user will use sudo to run the command su user as the root user. These options are documented under man sudo. The -u user option means to run the command as the specified user rather than root. The -s option means to run the shell specified in the environment variable SHELL if this has been set, or else the user's login shell. Sudo -su user is short for sudo -s -u user.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |