1 .\" Copyright 1992 Rickard E. Faith (faith@cs.unc.edu)
2 .\" May be distributed under the GNU General Public License
5 .TH SHUTDOWN 8 "2 March 2000" "Linux 2.0" "Linux Programmer's Manual"
7 shutdown \- close down the system
12 .RB [ now | \fIhh\fP:\fIss\fP | +\fImins\fP ]
18 .RB [ now | \fIhh\fP:\fIss\fP | +\fImins\fP ]
24 .RB [ now | \fIhh\fP:\fIss\fP | +\fImins\fP ]
30 .RB [ now | \fIhh\fP:\fIss\fP | +\fImins\fP ]
36 .RB [ now | \fIhh\fP:\fIss\fP | +\fImins\fP ]
39 .\" " for emacs hilit19
42 prepares the system for a power down or reboot. A absolute or delta time
43 can be given, and periodic messages will be sent to all users warning of
44 the shutdown. If no message is specified on the command line,
46 will ask for a message to be sent, unless the
52 .B "shutdown -h -q now"
56 .B "shutdown -h -q -f now"
60 .B "shutdown -r -q now"
64 .B "shutdown -r -q -f now"
66 The default delta time, if none is specified, is 2 minutes.
68 Five minutes before shutdown (or immediately, if shutdown is less than five
71 file is created with a message stating that the system is going down and
72 that logins are no longer permitted. The
74 program will not allow non-superusers to login during this period. A
75 message will be sent to all users at this time.
77 When the shutdown time arrives,
79 notifies all users, tells
83 writes the shutdown time into the
85 file, kills all other processes on the system,
87 unmounts all the disks,
89 again, waits for a second, and then either terminates or reboots the
92 Prior to unmounting all discs, the \fBSIGQUIT\fP signal is sent to the
93 \fBinit\fP process, which will in turn exec \fBshutdown\fP(8). This
94 allows for clean unmounting, even if the old inode for the \fBinit\fP
95 process was unlinked. If the current process ID (PID) equals 1, then
96 \fBshutdown\fP(8) will pause forever.
100 Halt the system. Do not reboot. This option is used when powering down
107 Fast. When the system is rebooted, the file systems will not be checked.
108 This is arranged by creating
112 must detect (and delete).
115 Quiet. This uses a default broadcast message, and does not prompt the user
119 Reboot in single user mode. This is arranged by creating
120 .IR /etc/singleboot ,
123 detects (and deletes).
131 .I /etc/shutdown.conf
134 The configuration file \fI/etc/shutdown.conf\fP is used to determine
135 the action to take when halting the machine. The currently supported
136 file format is extremely primitive. The first line must contain two
137 strings separated by whitespace. The first string must be
138 \fBHALT_ACTION\fP and the second specifies the action you wish to take
139 on halt. The options allowed are:
142 This will simply halt the system. This is the default behaviour.
143 Note also that this is the fallback if another option fails.
146 This will use the kernel power shutdown facility. This is usually only
147 available on machines with Advanced Power Management (APM).
150 This specifies a command to run to shut down the power. The first
151 character must be a "/". Bear in mind that this command will be run
152 with only the root filesystem mounted (and it will be read-only), and
163 users are notified of shutdown only once or twice, instead of many times,
164 and at shorter and shorter intervals as "apocalypse approaches."
165 Some would construe this as a feature.
167 This page documents the version of
169 originally written by Peter Orbaek (poe@daimi.aau.dk).