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Allow staff Group to sudo
Instead use Use account names associated with a user. For this example, I will be designating adminstrative users under the staff group. To see the list of groups available to you use the command, cat /etc/group.
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The default settigs of fail2ban are usually good enough but you can also customize fail2ban to suit your needs.
After a day or so on the Internet you should start seeing people getting banned in the logs, /var/log/fail2ban.log. Here is an example of an ip getting banned and then after 10 minutes it unbans,
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