nologin -- System Administration

Lock out logins
/etc/nologin

login looks for file /etc/nologin before it permits a user to login in.  If
this file exists, login forbids the user to log in, and instead displays on
the terminal  the contents of  this file -- which,  presumably, explain why
logging in is now forbidden.

You should  create this file when  you wish to ``lock  out'' users during a
critical time,  such as when  backups are being  run or when  the system is
about  to be  shut down.   When the  critical time has  passed, be  sure to
remove it.

login cannot lock out the superuser root, even if nologin exists.  Nor will
it lock out the users named in the file /etc/trustme, should it exist.

See Also

Administering COHERENT,
login,
trustme

Notes

The script /etc/rc removes  /etc/nologin by default, on the assumption that
after you reboot, you once again  want users to be able to log in.  If this
is not a sound assumption, edit /etc/rc to change this behavior.

© 2012 by Stephen A. Ness