Hi all
I try to set up a server again, and noted this behaviour. It keeps me from knowing, what is going on.
grep -r auth.log /var/log/fail2ban.log
2022-11-30 14:10:37,177 fail2ban.filter [2063]: INFO Removed logfile: '/var/log/auth.log'
2022-11-30 14:12:20,498 fail2ban.filter [2131]: INFO Added logfile: '/var/log/auth.log' (pos = 0, hash = da39a3ee5e6b4b0d3255bfef95601890afd80709)
2022-11-30 16:19:16,458 fail2ban.filter [2131]: INFO Removed logfile: '/var/log/auth.log'
2022-11-30 16:20:35,253 fail2ban.filter [2107]: INFO Added logfile: '/var/log/auth.log' (pos = 0, hash = da39a3ee5e6b4b0d3255bfef95601890afd80709)
2022-11-30 17:00:07,365 fail2ban.filter [2107]: INFO Removed logfile: '/var/log/auth.log'
2022-11-30 18:59:47,332 fail2ban.filter [2115]: INFO Added logfile: '/var/log/auth.log' (pos = 0, hash = da39a3ee5e6b4b0d3255bfef95601890afd80709)
2022-11-30 21:35:40,305 fail2ban.filter [2115]: INFO Removed logfile: '/var/log/auth.log'
2022-11-30 22:14:10,287 fail2ban.filter [2104]: INFO Added logfile: '/var/log/auth.log' (pos = 0, hash = da39a3ee5e6b4b0d3255bfef95601890afd80709)
2022-12-01 14:37:05,402 fail2ban.filter [2104]: INFO Removed logfile: '/var/log/auth.log'
On the previous installation I believed, that the server had been hacked because of this behaviour.
Now I find that fail2ban does it on a fresh install. (devuan chimaera)

I have a logrotate stanza, which is taking care of the file .
While the logrotate keeps the information , fail2ban destroys it.
What is the reason to delete the file contents?
How can I suppress the deletion and creation by fail2ban on start stop events?