I created the script file -
#!/bin/sh
echo "my application is here"
./helloworld # helloworld is our application
after creating the script file i copied it in init.d
I gave the command chmod +x /etc/init.d/vcc_app (vcc_app is the name of script which I have created)
Then I gave the command ln -s /etc/init.d/vcc_app /etc/rc.d/vcc_app (rc.d is the run level directory)
But when i reboot the board my application is not executed automatically. Can anyone help me out?
Scripts that are in /etc/init.d need to be LSB-compliant.
If you simply want to automatically run commands at the end of the boot process, try placing them in /etc/rc.local instead.
Not all linux systems use the same init daemon (ubuntu uses upstart: http://upstart.ubuntu.com/getting-started.html), but they all use start and stop functions in the script. Other common functions are status and restart, but again, there is no true across the board standard. Eg:
!#/bin/sh
start () {
echo "application started";
./helloworld # you should use an absolute path here instead of ./
}
stop () {
}
case "$1" in
start)
start
;;
stop)
stop
;;
*)
echo "Usage start|stop";
esac
exit $?
The last bit is a switch based on the first command line arg, since init will invoke the script myrcscript start.
In order to use stop() (and the also often useful restart()) you need to keep, or be able to get, the pid of the process launched by start(); sometimes this is done with a little "pid file" in /tmp (text file containing the pid, eg, /tmp/myscript.pid created in start()).
The "upstart" init daemon used on Ubuntu has its own specific features, but unless you need to use them, just keep it stop/start minimal and it will (probably) work anywhere.
Related
I am currently using the following command to run reboot
sudo shutdown -r now
however, I would need to run it for 5 loops before and after executing some other programs. Was wondering if it is possible to do it in MINT environment?
First a disclaimer: I haven't tried this because I don't want to reboot my machine right now...
Anyway, the idea is to make a script that can track it's iteration progress to a file as #david-c-rankin suggested. This bash script could look like this (I did test this):
#!/bin/sh
ITERATIONS="5"
TRACKING_FILE="/path/to/bootloop.txt"
touch "$TRACKING_FILE"
N=$(cat "$TRACKING_FILE" | wc -c)
if [ "$N" -lt "$ITERATIONS" ]; then
printf "." >> "$TRACKING_FILE"
echo "rebooting (iteration $N)"
# TODO: this is where you put the reboot command
# and anything you want to run before rebooting each time
else
rm "$TRACKING_FILE"
# TODO: other commands to resume anything required
fi
Then add a call to this script somewhere where it will be run on boot. eg. cron (#reboot) or systemd. Don't forget to remove it from a startup/boot command when you're finished or next time you reboot, it will reboot N times.
Not sure exactly how you are planning on using it, but the general workflow would look like:
save script to /path/to/reboot_five_times.sh
add script to run on boot (cron, etc.)
do stuff (manually or in a script)
call the script
computer reboots 5 times
anything in the second TODO section of the script is then run
go back to step 3, or if finished remove from cron/systemd so it won't reboot when you don't want it to.
First create a text document wherever you want,I created one on Desktop,
Then use this file as a physical counter and write a daemon file to run things at startup
For example:
#!/bin/sh
var=$(cat a.txt)
echo "$var"
if [ "$var" != 5 ]
then
var=$((var+1))
echo "$var" > a.txt
echo "restart here"
sudo shutdown -r now
else
echo "stop restart"
echo 0 > a.txt
fi
Hope this helps
I found a way to create a file at startup for my reboot script. I incorporated it with the answers provided by swalladge and also shubh. Thank you so much!
#!/bin/bash
#testing making a startup application
echo "
[Desktop Entry]
Type=Application
Exec=notify-send success
Hidden=false
NoDisplay=false
X-GNOME-Autostart-enabled=true
Name[en_CA]=This is a Test
Name=This is a Test
Comment[en_CA]=
Comment=" > ~/.config/autostart/test.desktop
I create a /etc/rc.local file to execute user3089519's script, and this works for my case. (And for bootloop.txt, I put it here: /usr/local/share/bootloop.txt )
First: sudo nano /etc/rc.local
Then edit this:
#!/bin/bash
#TODO: things you want to execute when system boot.
/path/to/reboot_five_times.sh
exit 0
Then it works.
Don't forget edit /etc/rc.local and remove /path/to/reboot_five_times.sh when you done reboot cycling.
I want to use start-stop-daemon to stop the scripts it has started, but currently the scripts are not killed, and so I have resorted to hacking around it:
#!/bin/sh
case $1 in
start)
start-stop-daemon --start --background -c myapp --exec /home/myapp/dev-myapp.sh
;;
stop)
# couldn't get this to work - hacking around it
#start-stop-daemon --stop -c myapp --exec /home/myapp/dev-myapp.sh
# hack
killall dev-myapp.sh
sleep 3
killall -9 dev-myapp.sh
;;
restart)
$0 stop
$0 start
;;
*)
echo "No such command. "
echo "Usage: $0 start|stop|restart"
esac
exit 0
How can I get the script to kill the bash scripts it has started using start-stop-daemon?
edit: I assume the failure to stop the processes has to do with this section from the man page:
-x, --exec executable
Check for processes that are instances of this executable. The executable argument should be an absolute pathname. Note: this
might not work as intended with interpreted scripts, as the executable will point to the interpreter. Take into account processes
running from inside a chroot will also be matched, so other match restrictions might be needed.
So I might be forced to rely on name detection instead, but I don't know what the process name is ... Is this the whole absolute filename, the filename alone, or something else?
Regarding your comment, if you're willing to extend the shellscript you are running, you can use a pidfile. In practice, maybe you want to make it an option to your script, but as an example, this line would be sufficient:
echo $$ >/var/run/dev-myapp.sh.pid
Then, use these matching parameters for start-stop-daemon, if necessary replacing /bin/bash with whatever shell executes your script:
-p /var/run/dev-myapp.sh.pid -x /bin/bash
(To clarify: The process name of the script is that of the script interpreter, in your case, the shell)
I'm running Arch-based Manjaro Linux and wrote myself a little update program, that starts every 7 hours and runs completely in the background. This update program is started by systemd.
What I wanna know is: How can I prevent any system shutdown/reboot during the time this program runs no matter if the user just wants to turn it off or any program wants to do so.
The best would be, if any shutdown/reboot action wouldn't be cancelled but delayed instead, so when the update program has finished its run, the shutdown/reboot continues.
My systemd parts are:
uupgrades.timer
[Unit]
Description=UU Upgrades Timer
[Timer]
OnBootSec=23min
OnUnitActiveSec=7h
Unit=uupgrades.target
[Install]
WantedBy=basic.target
uupgrades.target
[Unit]
Description=UU Upgrades Timer Target
StopWhenUnneeded=yes
and in the folder uupgrades.target.wants
uupgrades.service
[Unit]
Description=UU Update Program
[Service]
Nice=19
IOSchedulingClass=2
IOSchedulingPriority=7
ExecStart=/usr/bin/uupgrades
How can I achieve this?
If a user with sufficient permissions to reboot the server or manipulate processes wants to stop or reboot the machine you cant stop them. That's just how linux works. You should set up permissions and accounts such that no other users have root permissions or permissions sufficient to manipulate the process or user that the process is running as.
When I want to block myself from rebooting or shutdown, I alias my usual shutdown and reboot aliases to beep;beep;beep;.
In multiuser environments you could move the reboot, shutdown etc. binaries and move them back, when shutdown should be allowed again.
You could also temporarily move an executable shell script outputting information about the postponed shutdown possibility in place of the corresponding binaries. This script could set a flag, if a shutdown was requested.
Q&D example script:
#!/usr/bin/env bash
echo "preventing reboot"
BACKUPBINARY_REBOOT=$(mktemp);
mv /bin/reboot $BACKUPBINARY_REBOOT;
FLAGFILE=$(mktemp);
echo '#!/usr/bin/env bash' > /bin/reboot;
echo '# original reboot binary was moved to'"$BACKUPBINARY_REBOOT" >> /bin/reboot;
echo 'echo request-reboot > '"$FLAGFILE" >> /bin/reboot;
echo 'echo reboot is prevented, your request will trigger later' >> /bin/reboot;
chmod 666 "$FLAGFILE";
chmod +x /bin/reboot;
echo "postponed reboot - press enter to allow it again and make up for requested reboot";
read;
mv "$BACKUPBINARY_REBOOT" /bin/reboot;
if grep -q request-reboot "$FLAGFILE"; then
rm $FLAGFILE;
/bin/reboot;
fi
You can add another systemd service at /usr/lib/systemd/system-shutdown/ which will be run at shutdown, and have it check if your update script is running, and if so, cancel or delay the shutdown.
I want to send an email when the system is going to shutdown to an email ID. I have CentOS 6.4. Below is my Script.
cat /ect/init.d/sendshtmail
#!/bin/bash
EMAIL="example#example.com"
SHUTDOWNSUBJECT="["`hostname`"] - System Shutdown"
SHUTDOWNBODY="This is an automated message to notify you that "`hostname`" is shutting down.
LOCKFILE=/var/lock/subsys/SystemEmail
echo "${SHUTDOWNBODY}" | mutt -s "${SHUTDOWNSUBJECT}" ${EMAIL}
It has the appropriate permission. While running it manually it's working perfectly. I have just symlinked it to /etc/rc0.d/ folder. By issuing below command.
ln -s /etc/init.d/sendshtmail /etc/rc0.d/K00sendshtmail
But the script is not sending any email during shutdown. Thanks in Advance.
Place your shell script in /etc/init.d with executable permission and symlink name should start with K##. If you want to execute your script at first place immediately after shut down then name it with K00scriptname. Script started will K will be executed first based on ascending order then script with S.
ln -s /etc/init.d/script /etc/rc0.d/K00scriptname
Shutdown command will send the stop signal to script, your script (K00scriptname) should have stop function like example
stop()
{
echo "executing scriptname"
"Your script logic"
}
case "$1" in
stop)
stop
;;
esac
Most important, K00scriptname will execute only if there would be lock file present in /var/lock/subsys folder, so do "touch /var/lock/subsys/scriptname" then check by doing shutdown.
Try to set executable permissions for your script. Sometimes you need to do that to activate it.
chmod 755 /etc/init.d/sendshtmail
Also try to use absolute paths for your command, while quoting the other variable as well.
echo "${SHUTDOWNBODY}" | /usr/bin/mutt -s "${SHUTDOWNSUBJECT}" "${EMAIL}"
Another attempt is to switch your user to your current user e.g.
echo "${SHUTDOWNBODY}" | su -l -c "/usr/bin/mutt -s \"${SHUTDOWNSUBJECT}\" \"${EMAIL}\"" yourusername
ln -s /etc/init.d/sendshtmail /etc/rc0.d/S01sendshtmail
The symlink name should begin with a S - for Start (K for Kill)
The two-digit specifies the order of execution for your script, the lowest numbered being execute first.
I have several init.d scripts that I'm using to start some daemons. Most of these scripts I've found on the internet and they all use start-stop-daemon. My understanding is that "start-stop-daemon" is a command that is specific to Linux or BSD distros and is not available on Solaris.
What is the best way to translate my init.d scripts from Linux to Solaris? Is there a command equivalent to start-stop-daemon that I can use, roughly?
Since I'm not much of a Solaris user, I'm willing to admit upfront that I don't even know if my question is inherently invalid or not.
start-stop-daemon is a Linux thing, and not used that much on Solaris. I guess you can port the command though, if you want to reuse your init scripts.
Otherwise it depends on what version of Solaris you are using. Starting with Solaris 10 and also OpenSolaris they use a new startup script framework "Solaris Service Management Facility", which you configure with the commands svcs, svccfg and svcadm.
See http://www.oracle.com/technetwork/server-storage/solaris/overview/servicemgmthowto-jsp-135655.html for more information.
For older Solaris releases most init scripts are written in pure shell without any helper commands like start-stop-daemon.
On Solaris 10 or later using SMF is recommended, but on an earlier release you'd create an init script in /etc/init.d and link to it from the rcX.d directories. Here's a bare-bones example of an init script for launching an rsync daemon:
#!/sbin/sh
startcmd () {
/usr/local/bin/rsync --daemon # REPLACE WITH YOUR COMMANDS
}
stopcmd () {
pkill -f "/usr/local/bin/rsync --daemon" # REPLACE WITH YOUR COMMANDS
}
case "$1" in
'start')
startcmd
;;
'stop')
stopcmd
;;
'restart')
stopcmd
sleep 1
startcmd
;;
*)
echo "Usage: $0 { start | stop | restart }"
exit 1
;;
esac
Create a link to the script from each rcX.d directory (following the "S"/"K" convention).
ln rsync /etc/rc3.d/S91rsync
for i in `ls -1d /etc/rc*.d | grep -v 3`; do ln rsync $i/K02rsync; done
See the README in each rcX.d directory and check the man page for init.d. Here's a bit of the man page:
File names in rc?.d directories are of the form
[SK]nn, where S means start this job, K means
kill this job, and nn is the relative sequence number for killing or
starting the job.
When entering a state (init S,0,2,3,etc.) the rc[S0-6] script
executes those scripts in /etc/rc[S0-6].d that are prefixed with K
followed by those scripts prefixed with S. When executing each
script in one of the /etc/rc[S0-6] directories, the /sbin/rc[S0-6]
script passes a single argu- ment. It passes the argument 'stop'
for scripts prefixed with K and the argument 'start' for scripts
prefixed with S. There is no harm in applying the same sequence
number to multiple scripts.