This was the solution, not permanent, though:
rm -f /var/lib/rsyslog/imjournal.state systemctl restart rsyslog
ref: https://serverfault.com/questions/743003/logging-not-working-on-centos-7
/var/log/messages Logging not working on Centos 7
原文：http://www.cnblogs.com/pinganzi/p/7364910.html