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Centos java custom service

I have a script.sh that set some environment variable and start a java server.
#!/bin/bash
export JAVA_HOME="/opt/java"
export ....
nohup $JAVA_HOME/bin/java "$MEMORY_JAVA_OPS" -classpath "$MY_CLASSPATH" $MAIN_CLASS &
I would like to transform this script (now is launched by /etc/rc.d/rc.local) in a service.
I tried many examples found online and over StackOverflow.
I created myservice.service file using many templates found online... No one work!
one example is:
[Unit]
Description=MyService Java Process Restart Upstart Script
After=auditd.service systemd-user-sessions.service time-sync.target
[Service]
User=root
TimeoutStartSec=0
Type=simple
KillMode=process
#export JAVA_HOME=/opt/java/jdk-9
#export PATH=$PATH:$JAVA_HOME/bin
WorkingDirectory=/tmp/myworkdir
ExecStart=/path/to/myscript.sh
[Install]
WantedBy=multi-user.target
With some configurations, the service starts but the status command says that it is dead (while it is actually running). With others it does not start. With none it stops with the command stop ....
I tried Type=Simple, forking, oneshot... always some problem.
I would simply that after boot or when user launch systemctl start myservice, service start, and if after some time crash will be started again. And if I will run systemclt stop myservice it stops and not need to kill the process.

Firstly it need to be said, that concept "service" greatly differs in Linux/Unix and Windows environment. From your question seems to me you are looking for Unix solution.
In unix you typically register some statup and stop script/command. The startup script just runs your java application via java -jar app.jar. This application does business logic & also opens listening on some SHUTDOWN port.
The stop script/command just invokes another (or the same with different cmd parameters) java application which does nothing else just sending STOP command to original application's SHUTDOWN port.
You can look in more detail for example on tomcat startup/stop scripts - they are doing exactly this.
For windows is better to use some wrappers like WinRun4J or whatever else. Of course you can have one multiplatform maven archetype for "universal multiplatform" service like we do.
EDITED:
If you are still unsure how to configure it on Linux, read https://linuxconfig.org/how-to-create-systemd-service-unit-in-linux
ExecStart will be the startup java -jar app.jar and ExecStop will be the stopping command java -jar app-stopper.jar

Launch java application from inside eclipse with root privileges [duplicate]

I'm running in to an error when I try to run my server application from Eclipse. The error is java.net.BindException: Permission denied. I think this is because I am using port 443 to set up an SSL connection. I can get around this problem if I run my code on the command line using java and sudo. Is there a way to set up Eclipse so that when I hit the run button, my application is executed with sudo?

You can follow these steps to compile/debug applications as superuser.
Rename your java-application
sudo mv /usr/lib/jvm/java-6-openjdk/jre/bin/java /usr/lib/jvm/java-6-openjdk/jre/bin/java.ori
Create following script and store it as /usr/lib/jvm/java-6-openjdk/jre/bin/java
#!/bin/bash
# file: /usr/lib/jvm/java-6-openjdk/jre/bin/java
# descr: Starter for jdk. Runs jdk as root when
# cmd-line-arg "--run-as-root" is specified.
#
jre="/usr/lib/jvm/java-6-openjdk/jre/bin/java.ori"
run_as_root=false
args=
# Filter command-line argument
for arg in "$#"
do
case "$arg" in
--run-as-root) run_as_root=true
;;
*) args="$args $arg"
;;
esac
done
# Remove leading whitespaces
args=$(echo $args | sed -e 's/^[ \t]*//')
if $run_as_root
then
echo "WARNING: Running as root!"
gksu "$jre $args"
else
$jre $args
fi
Change the permissions to make it executable
sudo chmod 0755 /usr/lib/jvm/java-6-openjdk/jre/bin/java
Startup eclipse
Go to Window->Preferences->Java->Installed JREs
Duplicate java-6-openjdk to java-6-openjdk-root
Edit JRE and add "--run-as-root" as Default VM Argument
To run projects as root you need to follow these steps:
Go to Project->Properties->Java Build Path
Double-Click the JRE System Library and choose in Alternate JRE "java-6-openjdk-root"
Note: The idea is from http://www.eclipse.org/forums/index.php/mv/msg/87353/724852/#msg_724852

Assuming you are on Linux (*nix),
How about starting your eclipse session via a sudo command?
Such as
sudo ~/eclipse/eclipse
Now whatever you do from eclipse will have the sudo context?

As mentioned in this thread:
In order to open a port below 1024 on Unix/Linux systems you need to be
"root".
I also used the argument -Dorg.eclipse.equinox.http.jetty.port=8080 to change the listen port, but this seems to be ignored (according to the stacktrace)
Please use "-Dorg.osgi.service.http.port=8080".
As mentioned in HTTP Service:
org.osgi.service.http.port - specifies the port number to use for the http serving. The default value for this property is 80 (which requires root permission), as per the OSGi specification.
org.osgi.service.http.port.secure - specifies the port number to use for secure http serving. The default value for this property is 443 (which requires root permission), as per the OSGi specification.
Maybe if you try to modify that last property to a value above 1024 it could work without requiring any special privilege.

Another option would be to use iptables or ipfilter to forward port 80 to a port above 1024.
(Can someone contribute a link to a practical and easy-to-understand explanation ?)

A better answer, perhaps, if this serves your needs AND is possible, could be simple port redirection on your router.
Instead of trying to force your linux/unix to open a reserved port, when you are only developing this now (not installing) and you want to run it in a debugger,
set your router to redirect incoming (external) port 443 to a port that is more convenient for your current needs (say 4443).
I think most routers support this, and if yours doesn't it gives your mum a good christmas or birthday present idea!

I am writing C not Java but this should work in either case.
I use remote debug - define a "remote" connection to LOCALHOST which allows you to specify the user you will connect with, specify ROOT. Then define a Remote Application in debug configuration connection: LOCALHOST. Be sure to check "skip download to target path" at the bottom of the main tab as well as under the connection properties window.

You can use Remote Java Application mechanism for this.
Create Debug configuration for Remote Java Application
section in Run -> Debug configurations...
Set your project name
Choose Connection type as Standard (Socket Attach)
Configure Connection properties parameters for your binding
(for you it will be localhost and 443).
Set breakpoint in your app (e.g. at the beginning of the main method)
Run your app from terminal as superuser with following command: java -Xdebug -Xrunjdwp:transport=dt_socket,server=y,address=443 MyApp
Hit debug button in Eclipse for early created Remote Java Application
You code should be stopped on breakpoint in Eclipse!

If you use External tools (Run menu/External tools or an icon next to the Run/Debug icons on the toolbar), you can use any scripts or whatever you like. The scripts may give you elevated rights, or whatever.
On the other hand, this way debugging the application can become very hard, as neither the Run nor Debug commands get associated with this External tool configuration. Maybe it is possible to connect the Eclipse debugger of the application, but I don't know, how that is possible.

You may go this way
create a Makefile with javac calls
add the following line:
setcap 'cap_net_admin=+ep' Server
configure sudo to allow your Eclipse user to run setcap.
So you will have a transparent debugging (no sudo wrapper - gdb ok).
Cons: it is a local security breach.
Solution:
put this to /opt/my-stupid-eclipse
#!/bin/sh
setcap 'cap_net_admin=+ep cap_net_raw=+ep' $1
chmod +x this script and whitelist it on sudo config.
username ALL=(ALL) NOPASSWD: /opt/my-stupid-eclipse
Add it to your makefile, specify path to your Server binary.
Now you have pretty strange but secure script, that cannot be changed by other users... and still a little breach for replacing Server binary with any malicious code, that will gain caps, so no filename check/stricts will help.. can $1 be contaminated with bash commands, no? Guess, no.

How to change max open files limit(s) for spring-boot init.d service

Trying to change default open file limit value for spring-boot application (in Debian based system), which is started as init (System V) script, but I have difficulties finding a solution:
General recommendation is to add ulimit -n line to /etc/init.d/. Not possible, since in spring-boot case it's just a symlink to jar file.
spring-boot itself does not provide environment property or any convenient mechanism to do that.
/etc/security/limits.conf is not a solution either (does not effect daemons started during init)
Any ideas? Thanks

I am not a spring-boot expert, but the (awesome) fact that you can simply create a symlink should not mean that you have to do it. Simple init script like this should do:
[root#localhost app]# cat /etc/init.d/myapp
#!/bin/bash
ulimit -n 50001
/var/myapp/myapp.jar $1

How do I run my application as superuser from Eclipse?

I'm running in to an error when I try to run my server application from Eclipse. The error is java.net.BindException: Permission denied. I think this is because I am using port 443 to set up an SSL connection. I can get around this problem if I run my code on the command line using java and sudo. Is there a way to set up Eclipse so that when I hit the run button, my application is executed with sudo?

You can follow these steps to compile/debug applications as superuser.
Rename your java-application
sudo mv /usr/lib/jvm/java-6-openjdk/jre/bin/java /usr/lib/jvm/java-6-openjdk/jre/bin/java.ori
Create following script and store it as /usr/lib/jvm/java-6-openjdk/jre/bin/java
#!/bin/bash
# file: /usr/lib/jvm/java-6-openjdk/jre/bin/java
# descr: Starter for jdk. Runs jdk as root when
# cmd-line-arg "--run-as-root" is specified.
#
jre="/usr/lib/jvm/java-6-openjdk/jre/bin/java.ori"
run_as_root=false
args=
# Filter command-line argument
for arg in "$#"
do
case "$arg" in
--run-as-root) run_as_root=true
;;
*) args="$args $arg"
;;
esac
done
# Remove leading whitespaces
args=$(echo $args | sed -e 's/^[ \t]*//')
if $run_as_root
then
echo "WARNING: Running as root!"
gksu "$jre $args"
else
$jre $args
fi
Change the permissions to make it executable
sudo chmod 0755 /usr/lib/jvm/java-6-openjdk/jre/bin/java
Startup eclipse
Go to Window->Preferences->Java->Installed JREs
Duplicate java-6-openjdk to java-6-openjdk-root
Edit JRE and add "--run-as-root" as Default VM Argument
To run projects as root you need to follow these steps:
Go to Project->Properties->Java Build Path
Double-Click the JRE System Library and choose in Alternate JRE "java-6-openjdk-root"
Note: The idea is from http://www.eclipse.org/forums/index.php/mv/msg/87353/724852/#msg_724852

Assuming you are on Linux (*nix),
How about starting your eclipse session via a sudo command?
Such as
sudo ~/eclipse/eclipse
Now whatever you do from eclipse will have the sudo context?

As mentioned in this thread:
In order to open a port below 1024 on Unix/Linux systems you need to be
"root".
I also used the argument -Dorg.eclipse.equinox.http.jetty.port=8080 to change the listen port, but this seems to be ignored (according to the stacktrace)
Please use "-Dorg.osgi.service.http.port=8080".
As mentioned in HTTP Service:
org.osgi.service.http.port - specifies the port number to use for the http serving. The default value for this property is 80 (which requires root permission), as per the OSGi specification.
org.osgi.service.http.port.secure - specifies the port number to use for secure http serving. The default value for this property is 443 (which requires root permission), as per the OSGi specification.
Maybe if you try to modify that last property to a value above 1024 it could work without requiring any special privilege.

Another option would be to use iptables or ipfilter to forward port 80 to a port above 1024.
(Can someone contribute a link to a practical and easy-to-understand explanation ?)

A better answer, perhaps, if this serves your needs AND is possible, could be simple port redirection on your router.
Instead of trying to force your linux/unix to open a reserved port, when you are only developing this now (not installing) and you want to run it in a debugger,
set your router to redirect incoming (external) port 443 to a port that is more convenient for your current needs (say 4443).
I think most routers support this, and if yours doesn't it gives your mum a good christmas or birthday present idea!

I am writing C not Java but this should work in either case.
I use remote debug - define a "remote" connection to LOCALHOST which allows you to specify the user you will connect with, specify ROOT. Then define a Remote Application in debug configuration connection: LOCALHOST. Be sure to check "skip download to target path" at the bottom of the main tab as well as under the connection properties window.

You can use Remote Java Application mechanism for this.
Create Debug configuration for Remote Java Application
section in Run -> Debug configurations...
Set your project name
Choose Connection type as Standard (Socket Attach)
Configure Connection properties parameters for your binding
(for you it will be localhost and 443).
Set breakpoint in your app (e.g. at the beginning of the main method)
Run your app from terminal as superuser with following command: java -Xdebug -Xrunjdwp:transport=dt_socket,server=y,address=443 MyApp
Hit debug button in Eclipse for early created Remote Java Application
You code should be stopped on breakpoint in Eclipse!

If you use External tools (Run menu/External tools or an icon next to the Run/Debug icons on the toolbar), you can use any scripts or whatever you like. The scripts may give you elevated rights, or whatever.
On the other hand, this way debugging the application can become very hard, as neither the Run nor Debug commands get associated with this External tool configuration. Maybe it is possible to connect the Eclipse debugger of the application, but I don't know, how that is possible.

You may go this way
create a Makefile with javac calls
add the following line:
setcap 'cap_net_admin=+ep' Server
configure sudo to allow your Eclipse user to run setcap.
So you will have a transparent debugging (no sudo wrapper - gdb ok).
Cons: it is a local security breach.
Solution:
put this to /opt/my-stupid-eclipse
#!/bin/sh
setcap 'cap_net_admin=+ep cap_net_raw=+ep' $1
chmod +x this script and whitelist it on sudo config.
username ALL=(ALL) NOPASSWD: /opt/my-stupid-eclipse
Add it to your makefile, specify path to your Server binary.
Now you have pretty strange but secure script, that cannot be changed by other users... and still a little breach for replacing Server binary with any malicious code, that will gain caps, so no filename check/stricts will help.. can $1 be contaminated with bash commands, no? Guess, no.

How to write init script

Hi I am using 64bit Fedora 10 linux. I have created a sample java application. Now I want to write init script for that application. so that my application should start on bootup.
How to write init script to start on bootup.
Thanks
Sunil Kumar Sahoo

There's quite a good guide here:
http://www.novell.com/coolsolutions/feature/15380.html
I'd suggest taking a look at the tomcat startup.sh and shutdown.sh scripts, and then modifying the following init.d script:
#!/bin/bash
#
# tomcat
#
# chkconfig:
# description: Start up the Tomcat servlet engine.
# Source function library.
. /etc/init.d/functions
RETVAL=$?
CATALINA_HOME="/usr/apps/apache/tomcat/jakarta-tomcat-4.0.4"
case "$1" in
start)
if [ -f $CATALINA_HOME/bin/startup.sh ];
then
echo $"Starting Tomcat"
/bin/su tomcat $CATALINA_HOME/bin/startup.sh
fi
;;
stop)
if [ -f $CATALINA_HOME/bin/shutdown.sh ];
then
echo $"Stopping Tomcat"
/bin/su tomcat $CATALINA_HOME/bin/shutdown.sh
fi
;;
*)
echo $"Usage: $0 {start|stop}"
exit 1
;;
esac
The above script is missing much of the stuff to make it fully Linux Standard Base compliant. You may want to copy an existing init.d script from your distro. A slightly better script can be found here: http://blog.valotas.com/2011/05/tomcat-initd-script.html

I usually just take one of the smaller init scripts from /etc/init.d and modify it.
Edit
The easiest thing to do is just add your program to the /etc/rc.local file. It will be the last start script executed. You won't have to mess around with the "start" and "stop" stuff.
However, if you're interested in being able to start and stop your program at will, you'll need to write a script.
Some of the other answers here will get you started.

Many distributions come with a skeleton script you can use as a template for your own init script, in /etc/init.d/skeleton or /etc/init.d/skel.

Some of the best java applications that I have seen tend to use the tanuki wrapper for this.
It standardises startup scripts across different OS's, i.e. can be used to configure a *nix daemon or a windows service.
It provides a standard command line interface for stopping, starting, restarting and checking the status - running or not.
I appreciate seeing it used more and more, as I don't have to learn it again, learn it once and reuse it again and again.
By using this service library, your application can benefit from future enhancements.