Where i can find the logs in aggregate?

What is the problem? Please be detailed.
I'm getting "Failure - will retry later" error when exporting into json. I would like to check what's the actual problem. Where i can find the logs of aggregate installation in my tomcat server?.

Depends on the OS and how you installed Tomcat. Can you share that info?

I'm using tomcat 8.5 on a CentOs based system.

I'm not super familiar with CentOS, but it's probably in /var/log/tomcat.