I have a systemd service file which is directly calling a shell script. My expectation is that stdout and stderr from the file would be captured by journal+console, but it is only appearing in syslog. What should I change in my service file or the script file such that it behaves as expected?
The service file looks like:
[Unit]
Description=Test
After=network-online.target
Wants=network-online.target
[Service]
Type=simple
Restart=always
RestartSec=5min
TimeoutSec=5min
GuessMainPID=no
ExecStart=/tmp/script start systemd
ExecStop=/tmp/script stop systemd
SuccessExitStatus=143
User=test
Group=test
LimitAS=infinity
LimitRSS=infinity
LimitNPROC=4096
LimitNOFILE=65536
StandardOutput=journal+console
[Install]
WantedBy=multi-user.target graphical.target
The script actually invokes a jar but to simplify let's consider a simpler version:
#!/bin/sh
echo "ERROR: Java not found"
exit 1
Using systemd-cat and logger I was able to direct echo statement to systlog and journald, still the log did not show up on the console.
What is the correct way to direct stdout and stderr to journal+console?
Related
I am tweaking snmpd systemd service and I want to execute a script in ExecStartPost. This will be an infinite loop script.
This script is an implementation of agentx ..
I have tried running in a normal manner with and without & , but after sometime the systemd service is timing out..
it is timing out expecting a exit status from the script is what is believe.
Is there any way to run the script in background without the systemd snmp service timing out ?
[Unit]
Description=Simple Network Management Protocol (SNMP) Daemon.
After=syslog.target network.target
[Service]
Type=notify
Environment=OPTIONS="-LS0-6d"
EnvironmentFile=-/etc/sysconfig/snmpd
ExecStart=/usr/sbin/snmpd $OPTIONS -f
ExecStartPost=/usr/bin/python /usr/local/bin/pyagent.py
ExecReload=/bin/kill -HUP $MAINPID
[Install]
WantedBy=multi-user.target
From reading the documentation, I believe you want to keep your & but add - prefix to skip result checking:
ExecStartPost=-/usr/bin/python /usr/local/bin/pyagent.py &
I made a systemd service that should run a script on startup. The script contains a couple echoes for power saving and a command to disable my bluetooth. It has executable rights.
When I start the service it has an inactive (dead) status.
Here you can see my systemd service and the script that i am trying to run.
I already tried a crontab : #reboot ( sleep 90 ; sh /home/maxim/bin/power.sh )
Still didn't have the required results.
[Unit]
Description=Example systemd service.
[Service]
Type=simple
ExecStart=/usr/bin/sudo /bin/sh /home/maxim/bin/power.sh
[Install]
WantedBy=default.target
The power.sh script:
#!/bin/bash
echo 'min_power' > '/sys/class/scsi_host/host2
/link_power_management_policy'
echo 'min_power' > '/sys/class/scsi_host/host3
/link_power_management_policy'
echo 'min_power' > '/sys/class/scsi_host/host0
/link_power_management_policy'
echo 'min_power' > '/sys/class/scsi_host/host1
/link_power_management_policy'
echo '1500' > '/proc/sys/vm/dirty_writeback_centisecs'
rfkill block bluetooth
I'm running embedded linux on an Altera FPGA. It uses SystemD to run startup, and I have a script in the "multi-user.target.wants" section that runs my application.
When it runs from startup my code runs slower than when I run the identical script from an ssh shell.
I have checked that paths are the same, that permissions are correct on the scripts, that full paths are used in the scripts. Using 'top' I can see that priorities are set the same for the various threads started, yet somehow performance is completely different between the two ways of starting.
The script in full is:
#!/bin/sh
sleep 5s
mount /dev/mmcblk0p5 /home/root/linux
cd /home/root/linux/mem_driver
./memdev_load
cd /home/root/linux/gpio_driver
insmod ./gpiodev.ko
mknod /dev/gpiodev c 249 0
sleep 5s
cd /home/root/src/control
mysqld_safe &
up=0
while [ $up -ne 2 ]
do
up=$(pgrep mysql | wc -l);
echo $up
done
sleep 3s
cd /home/root/studio_web/myapp
npm start &
sleep 1s
cd /home/root/src/control
#sleep 1s
./control > /home/root/linux/output.log
various sleep commands have been inserted to try and make sure things start up in the right order.
Any help in diagnosing why this behaves differently would be greatly appreciated.
Is that the only shell script you are using? or do you have a systemd service file that executes that single shell script?
Using sleep is ineffective here. You should separate them into separate shell scripts and then use systemd to ensure that the shell scripts are run in order.
For example, we want to mount the directory first, because if this fails then nothing following will be successful. So we create a systemd mount service:
# home-root-linux.mount
[Unit]
Description=Mount /home/root/linux
Before=gpiodev.service
[Mount]
What=/dev/mmcblk0p5
Where=/home/root/linux
Options=defaults
[Install]
WantedBy=multi-user.target
Then we can create another systemd service which depends on the mount above before executing the three parts of the shell script which were previously separated by sleep to ensure that they were run in order.
# gpiodev.service
[Unit]
Description=Handle gpiodev kernel module
After=home-root-linux.mount
Before=mysqlsafe.service
[Service]
Type=oneshot
ExecStartPre=/home/root/linux/mem_driver/memdev_load
ExecStart=/sbin/insmod gpiodev.ko; /bin/mknod /dev/gpiodev c 249 0
WorkingDirectory=/home/root/linux/gpio_driver
RemainAfterExit=yes
StandardOutput=journal
[Install]
WantedBy=multi-user.target
Second part of the systemd service (following the sleep). We have a separate shellscript which is placed in /sbin/ in this example as it contains a while loop so it would be best to separate this:
# mysqlsafe.service
[Unit]
Description=MySQL safe
After=gpiodev.service
Before=npmoutput.service
[Service]
Type=oneshot
ExecStart=/sbin/mysqlsafe.sh
WorkingDirectory=/home/root/src/control
RemainAfterExit=yes
StandardOutput=journal
[Install]
WantedBy=multi-user.target
Second part of the shell script which is executed in the systemd service above (separated to a separate file due to the complexity):
# /sbin/mysqlsafe.sh
#!/bin/sh
mysqld_safe &
up=0
while [ $up -ne 2 ]
do
up=$(pgrep mysql | wc -l);
echo $up
done
Third part of the systemd service (the third section of the original shell script which was separated by sleep):
# mpmoutput.service
[Unit]
Description=npm and output to log
After=mysqlsafe.service
[Service]
Type=oneshot
ExecStartPre=/usr/bin/npm &
ExecStart=/home/root/src/control > /home/root/linux/output.log
WorkingDirectory=/home/root/studio_web/myapp
RemainAfterExit=yes
StandardOutput=journal
[Install]
WantedBy=multi-user.target
The idea behind this approach is that systemd recognises the importance of each service and the reliance upon the following service i.e. if one service fails the following services in queue will not execute. You can then check this using systemctl and see logging in journalctl.
Just a quick copy, paste and edit. Could contain errors as it was not tested or checked.
More reading can be found here regarding systemd service files: https://www.freedesktop.org/software/systemd/man/systemd.service.html
I have the following unit file:
[Unit]
Description=Startup Thing
[Service]
Type=simple
ExecStart=/bin/bash
StandardInput=tty
TTYPath=/dev/pts/19
What I am trying to do is pipe input from a terminal to /bin/bash. But for some reason the terminal kind of doesn't process my input correctly. When I type "ls", the terminal only shows the "l" and no "s"... this happens to all other commands as well. What am I doing wrong?
I need to run a java jar in server in order to communicate between two applications. I have written two shell scripts to run it, but once I start up that script I can't shut down / terminate the process. If I press ctrl+C or close the console, the server will shut down. Could anyone help me how to modify this script to run as a normal server?
#!/bin/sh
java -jar /web/server.jar
echo $!
#> startupApp.pid
You can try this:
#!/bin/sh
nohup java -jar /web/server.jar &
The & symbol, switches the program to run in the background.
The nohup utility makes the command passed as an argument run in the background even after you log out.
Systemd which now runs in the majority of distros
Step 1:
Find your user defined services mine was at /usr/lib/systemd/system/
Step 2:
Create a text file with your favorite text editor name it whatever_you_want.service
Step 3:
Put following
Template to the file whatever_you_want.service
[Unit]
Description=webserver Daemon
[Service]
ExecStart=/usr/bin/java -jar /web/server.jar
User=user
[Install]
WantedBy=multi-user.target
Step 4:
Run your service
as super user
$ systemctl start whatever_you_want.service # starts the service
$ systemctl enable whatever_you_want.service # auto starts the service
$ systemctl disable whatever_you_want.service # stops autostart
$ systemctl stop whatever_you_want.service # stops the service
$ systemctl restart whatever_you_want.service # restarts the service
If you're using Ubuntu and have "Upstart" (http://upstart.ubuntu.com/) you can try this:
Create /var/init/yourservice.conf
with the following content
description "Your Java Service"
author "You"
start on runlevel [3]
stop on shutdown
expect fork
script
cd /web
java -jar server.jar >/var/log/yourservice.log 2>&1
emit yourservice_running
end script
Now you can issue the service yourservice start and service yourservice stop commands. You can tail /var/log/yourservice.log to verify that it's working.
If you just want to run your jar from the console without it hogging the console window, you can just do:
java -jar /web/server.jar > /var/log/yourservice.log 2>&1
Run in background and add logs to log file using the following:
nohup java -jar /web/server.jar > log.log 2>&1 &