什么fail2ban正则expression式会捕获这样的日志？
Apr 9 08:48:28 server sshd[1856]: Received disconnect from 43.255.190.117: 11: [preauth] Apr 9 09:06:05 server sshd[1936]: Received disconnect from 43.255.191.159: 11: [preauth] Apr 9 09:06:10 server sshd[1938]: Received disconnect from 43.255.190.126: 11: [preauth] Apr 9 09:31:12 server sshd[2005]: Received disconnect from 43.255.190.123: 11: [preauth] Apr 9 09:37:06 server sshd[2013]: Received disconnect from 43.255.190.149: 11: [preauth] Apr 9 09:53:55 server sshd[2036]: Received disconnect from 43.255.190.149: 11: [preauth] Apr 9 10:16:59 server sshd[2368]: Received disconnect from 43.255.190.165: 11: [preauth] Apr 9 10:47:30 server sshd[3800]: Received disconnect from 43.255.190.150: 11: [preauth] Apr 9 11:04:01 server sshd[6855]: Received disconnect from 43.255.190.131: 11: [preauth] 和/或再见
Apr 9 12:29:59 server sshd[7764]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:00 server sshd[7766]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:01 server sshd[7768]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:03 server sshd[7776]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:04 server sshd[7778]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:05 server sshd[7780]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:06 server sshd[7782]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:07 server sshd[7784]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:08 server sshd[7786]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:10 server sshd[7788]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:11 server sshd[7790]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:12 server sshd[7792]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:13 server sshd[7794]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:14 server sshd[7796]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:15 server sshd[7798]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth] Apr 9 12:30:17 server sshd[7800]: Received disconnect from 180.210.234.87: 11: Bye Bye [preauth]
无论这些人在做什么，我都想要一个fail2ban规则。 显然他们没有做任何其他的事情fail2ban，尽pipe尝试的频率。
你可以使用这个规则：
^%(__prefix_line)sReceived disconnect from <HOST>: 11: (Bye Bye)? \[preauth\]$
要用fail2ban-regex或egrep来testing它，你可以^%(__prefix_line)s开始^%(__prefix_line)s 。 将此行添加到/etc/fail2ban/filter.d/sshd.conf的failregexvariables中。
fail2ban-regex运行给了我这些结果，确认规则匹配：
Running tests ============= Use regex file : sshd.conf Use log file : /var/log/auth.log Results ======= Failregex |- Regular expressions: [...] | [11] ^\s*(?:\S+ )?(?:kernel: \[\d+\.\d+\] )?(?:@vserver_\S+ )?(?:(?:\[\d+\])?:\s+[\[\(]?sshd(?:\(\S+\))?[\]\)]?:?|[\[\(]?sshd(?:\(\S+\))?[\]\)]?:?(?:\[\d+\])?:)?\s*Received disconnect from <HOST>: 11: (Bye Bye)? \[preauth\]$ | `- Number of matches: [...] [11] 545 match(es) [...]