How to grant a java tool write permission to /var/log?

Question

I'm running a java tool as a command line app using cronjob: java -jar /var/java/-myfile.jar

By default I'm using logback and write to /var/log/mylogfile.log.

Problem: the user running the jar has no permissions to write to the /var/log/ folder. That folder has only permissions to `root syslog'.

Question: should I run the jar as sudo? Or should I give the running user write permissions to that folder? If yes, how?

Solution

Should I run the jar as sudo?

No. Far too dangerous since you could then change about anything to the system and a single misplaced space could remove your whole system.

Or should I give the running user write permissions to that folder? If yes, how?

Yes. The 2 main commands are to change write permissions and change the USER of your log file:

   sudo chmod 664 /var/log/{yourdir}/mylogfile.log
   sudo chown $USER:$USER /var/log/{yourdir}/mylogfile.log

where $USER is your current active user and {yourdir}/ is a directory you defined (mysql and apache for instance use their own directory in /var/log/ instead of filling up /var/log/). It is a slightly better method.

Comments

[ridgy]

Don't run the .jar as sudo; every mistake (wrong paths e.g.) could destroy your system. As syslog has write access, you might add the user to that group: adduser <user> syslog.

[membersound]

Thanks for you opinion. You might want to add this as an answer, so I could accept it lateron?

[Hindol]

Might be slightly better to actually create a directory within /var/log and change ownership of that directory as this allows the app to create or re-create the log file.

[Rinzwind]

I agree :) editted.