On RHEL7, up until tomcat v7.0.59 Redhat maintained backwards compatibility with RHEL6 structures. Once you upgrade to tomcat 7.0.70-x all that changes. Two things specifically:
One big change is the use of $CATALINA_OPTS, if you have multiple lines defining various $CATALINA_OPT properties your installation will break. Once you upgrade you must specify all of your $CATALINA_OPTS on a single line. This has to do with the use of systemd, regardless all on one line or it won’t work.
Ensure tomcat7 is logging to /var/log/tomcat7/catalina.out
Create a new file /etc/rsyslog.d/tomcat.conf containing the next two lines:
programname,contains,"server" /var/log/tomcat/catalina.out programname,contains,"server" ~
Afterwards, restart the rsyslog daemon:
service rsyslog restart
Those are the only issues I have found yet, I’ll update if more surface.