Hello,
I upgraded today my nextcloud from 11.0.3 to 12.0.2 and have the same warning messages regarding “client denied”.
The problem itself isn’t so big, but fail2ban bans me after hitting that point several times!
So it is not harmless at all. After 5 tries, I get a ban. After 5 bans, i am out for a week.
Thanks for an answer
Peter