1.\" Copyright (c) 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 4. Neither the name of the University nor the names of its contributors 13.\" may be used to endorse or promote products derived from this software 14.\" without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26.\" SUCH DAMAGE. 27.\" 28.\" @(#)nologin.8 8.1 (Berkeley) 6/19/93 29.\" $FreeBSD: src/usr.sbin/nologin/nologin.5,v 1.15 2007/05/10 11:22:24 yar Exp $ 30.\" $DragonFly: src/sbin/nologin/nologin.5,v 1.4 2008/01/04 18:17:49 swildner Exp $ 31.\" 32.Dd May 10, 2007 33.Dt NOLOGIN 5 34.Os 35.Sh NAME 36.Nm nologin 37.Nd disallow logins 38.Sh DESCRIPTION 39Programs such as 40.Xr login 1 41disallow logins if the 42.Nm 43file exists. 44The programs display the contents of 45.Nm 46to the user if possible and interrupt the login sequence. 47This makes it simple to temporarily prevent incoming logins systemwide. 48.Pp 49To disable logins on a per-account basis, 50investigate 51.Xr nologin 8 . 52.Sh SECURITY 53The 54.Nm 55file is ignored for user root by default. 56.Sh IMPLEMENTATION NOTES 57The 58.Nm 59feature is implemented through 60.Xr login.conf 5 , 61which allows to change the pathname of the 62file and to extend the list of users 63exempt from temporary login restriction. 64.Pp 65PAM-aware programs can be selectively configured to respect 66.Nm 67using the 68.Xr pam_nologin 8 69module via 70.Xr pam.conf 5 . 71.Sh FILES 72.Bl -tag -width ".Pa /var/run/nologin" -compact 73.It Pa /var/run/nologin 74default location of 75.Nm 76.El 77.Sh SEE ALSO 78.Xr login 1 , 79.Xr login.conf 5 , 80.Xr pam.conf 5 , 81.Xr rc.conf 5 , 82.Xr nologin 8 , 83.Xr pam_nologin 8 , 84.Xr shutdown 8 85