Whenever you try to connect your server to the Internet, you pose a threat to the storage space, connectivity of the network, and commute resource, which when combined, are the server itself. These elements are exposed to the considerable danger even before any application is run on the server, which, in turn, can further deteriorate the situation. However, there is Fail2Ban, a solution that is capable of foiling attempts of malicious connecting.
If your server is not properly protected, there is little chance that hackers will not take advantage of it. The lack of security measures will result in spam to hundreds and thousands of Internet users, infection with malware, and another botnet for phishing attacks. With an aim to do these things, online criminals challenge the security of servers with public IP address through the attempts to log in, port scans, and probes.
Moreover, hackers create systems that automatically search for susceptibilities and, as brute-force bots, for instance, sort out logins and passwords. If the authentication made this way is successful, the server is in jeopardy. If the password is strong and long enough, such attacks cause no substantial damage. Still, they may disrupt the working process and frustrate the user as they increase bandwidth usage and deplete other server resources.
A timely detection of these attempts is the best way to render them harmless. For this purpose, automatically generated logs are applied. They are the records of the data on connections with both favorable and unfavorable outcomes and IP address of a server trying to get connected. If a specific IP makes efforts to log in surprisingly many times but each time the credentials are incorrect, the server needs adequate protection. It is a vivid sign of malicious activity.
Fail2Ban checks server logs and identifies inconsistencies as those described above. If the security application considers a certain IP the one responsible for the attacks, it thwarts all further attempts by introducing a new firewall rule. Still, Fail2Ban is developed enough to detect more complicated and intricate dangers than brute force attacks. It is also flexible to a user’s parameters for banning, which can be easily adjusted. For example, if there are users who tend to input incorrect passwords, they may be banned after three subsequent failing attempts to log in but allowed to try again in fifteen minutes.
Fail2Ban is not the answer to all security problems related to servers since it is a small element of a complicated security system only. Besides, if you use the application, it does not mean that complex passwords are no longer needed. However, the tool is indeed effective in preventing and mitigating the effects of brute-force bot activity and automatic attempts to log in.