You should disable UseDNS by editing /etc/ssh/sshd_config and setting: UseDNS no
Otherwise, lfd will be unable to track SSHD login failures successfully as the log files will not report IP addresses
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This option is useless in 2023. UseDNS controls whether SSHD should not only resolve remote host names but also check whether the resolved host names map back to remote ip addresses. Default value is No which avoids login delays when the remote client’s DNS cannot be resolved.
Kindly read the documentation further to understand. In my opinion it just create an awful lot of time for the password prompt to show up for some users. There are better security measures to implement.