Hello @ish and thank you for your answer !
First, I did the upgrade. I should have paid attention to this before taking the tool back in hand.
Next, I replaced logging options correctly in suricata.yaml comparing with the default configuration file and I have no more errors about this.
For your suggestion, it was right. I didn’t have alert generating traffic. The fact is that the default-rule-path was pointing on a file which was empty. I don’t know when this happened and it looks weird to me. , I hadn’t thought of looking at this file because it hasn’t been modified since installation. 
So, with a simple ICMP test alert I could see everything was working. I feel stupid …
However, I’m having some new troubles with the different files containing the rules because I have some errors and warnings about their location.
This is no longer the subject of this topic and I already have one of your answers to help me.
(cf. "/var/lib/suricata/rules" directory or "/usr/share/suricata/rules/" directory? - #3 by ish)
I think I’ll be able to fix the problem.
Thanks for your help !