I'm trying to play with Fail2ban plugin and I don't understand the goal of "exclusion time" and "max retry" in the main parameters tab :
They seem to always be ignored and replaced by the same parameters under each jail service configuration which are not optional :
With the previous values, exclusion time is set to "forever" and cannot be left empty to use general parameter (1h).
Same for max retry... except I don't know what "-1" means. It seems it blocks account on each fail.
Another small issue is for the text attached to max retry (in jail tab). In french, it's translated in "Essai maximum en secondes" but, as I understood it's in occurrences, not in seconds.
And it's not a translation issue because in english, the text is the same :
Finally, last issue I had is the default MTA generated by OMV in /etc/fail2ban/jail.conf file.
It's set as "mta = sendmail" (the default for fail2ban), but as I remember sendmail is not installed on OMV by default (finally, not really sure, it's not a path issue...)
So to solve this, my 1st try was to install sendmail with "apt install sendmail" (DON'T DO THIS) without looking enough on packages impacts and, doing this, OMV is simply uninstalled...
Well, I solved this by reinstalling OMV and sendmail stays installed for me.
If sendmail is effectively not installed by default, better option would be to change OMV generated jail.conf file to use "mta = mail", no ?
As an alternative, on the user side, it's possible to create a local file for this :
and insert in this file :
then reload fail2ban with :
Sorry for this long mail and thank you for your advices.