output logs in crontab does not work I have a cron job it's on runnable .jar but I really want to check the output logs in console. but I wondered also if this command below will start to run on 3:15am but this jar takes time a lot of time to comple, Is there possibility that the current running will be overriden to the next schedule? need some clarifications. 15 3 * * * java -jar -Xmx4G -Xms256M /home/desktop/Documents/Run/New_Version/wine.jar batch >> /var/log/wine.log

The cron entry you specified will run at 3.15am (if the host is turned on) but there are a few things to check:

The usercontext of the job:

* Can it find the `java` binary to start? Consider using the absolute path to `java`.
* Does the user have access to write to `/var/log/wine.log`?



Output of `stderr`:

Consider to log the error output also using `2>&1` in your command so you can troubleshoot the cron run:


15 3 * * * java ... 2>&1 >> /var/log/wine.log


And have a look at the `cron` log (often part of syslog or messages log).