nologin(5) [osx man page]

NOLOGIN(5)						      BSD File Formats Manual							NOLOGIN(5)

NAME

     nologin -- disallow logins

DESCRIPTION

     Programs such as login(1) disallow logins if the nologin file exists.  The programs display the contents of nologin to the user if possible
     and interrupt the login sequence.	This makes it simple to temporarily prevent incoming logins systemwide.

     To disable logins on a per-account basis, investigate nologin(8).

SECURITY

     The nologin file is ignored for user root by default.

IMPLEMENTATION NOTES

     The nologin feature is implemented through login.conf(5), which allows to change the pathname of the file and to extend the list of users
     exempt from temporary login restriction.

     PAM-aware programs can be selectively configured to respect nologin using the pam_nologin(8) module via pam.conf(5).

     The nologin file will be removed at system boot if it resides in /var/run and cleanvar_enable is set to ``YES'' in rc.conf(5), which is
     default.  Therefore system reboot can effectively re-enable logins.

FILES

     /var/run/nologin  default location of nologin

SEE ALSO

     login(1), login.conf(5), pam.conf(5), rc.conf(5), nologin(8), pam_nologin(8), shutdown(8)

BSD
								   May 10, 2007 							       BSD

PAM_NOLOGIN(8)							 Linux-PAM Manual						    PAM_NOLOGIN(8)

NAME

       pam_nologin - Prevent non-root users from login

SYNOPSIS

       pam_nologin.so [file=/path/nologin] [successok]

DESCRIPTION

       pam_nologin is a PAM module that prevents users from logging into the system when /var/run/nologin or /etc/nologin exists. The contents of
       the file are displayed to the user. The pam_nologin module has no effect on the root user's ability to log in.

OPTIONS

       file=/path/nologin
	   Use this file instead the default /var/run/nologin or /etc/nologin.

       successok
	   Return PAM_SUCCESS if no file exists, the default is PAM_IGNORE.

MODULE TYPES PROVIDED

       The auth and acct module types are provided.

RETURN VALUES

       PAM_AUTH_ERR
	   The user is not root and /etc/nologin exists, so the user is not permitted to log in.

       PAM_BUF_ERR
	   Memory buffer error.

       PAM_IGNORE
	   This is the default return value.

       PAM_SUCCESS
	   Success: either the user is root or the nologin file does not exist.

       PAM_USER_UNKNOWN
	   User not known to the underlying authentication module.

EXAMPLES

       The suggested usage for /etc/pam.d/login is:

	   auth  required  pam_nologin.so

NOTES

       In order to make this module effective, all login methods should be secured by it. It should be used as a required method listed before any
       sufficient methods in order to get standard Unix nologin semantics. Note, the use of successok module argument causes the module to return
       PAM_SUCCESS and as such would break such a configuration - failing sufficient modules would lead to a successful login because the nologin
       module succeeded.

SEE ALSO

       nologin(5), pam.conf(5), pam.d(5), pam(7)

AUTHOR

       pam_nologin was written by Michael K. Johnson <johnsonm@redhat.com>.

Linux-PAM Manual						    09/19/2013							    PAM_NOLOGIN(8)