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Регулярное выражение для нескольких sshd Получено отключение от… [preauth]

Какое регулярное выражение fail2ban будет перехватывать такие журналы?

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]

и / или с Bye Bye

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]

Что бы ни делали эти люди, я бы хотел использовать для этого правило fail2ban. Судя по всему, они больше ничего не делают для отключения fail2ban, несмотря на частоту попыток.

Вы можете использовать это правило:

^%(__prefix_line)sReceived disconnect from <HOST>: 11: (Bye Bye)? \[preauth\]$

Чтобы проверить это с помощью fail2ban-regex или egrep, вы можете просто снять ^%(__prefix_line)s с начала. Добавьте эту строку в failregex переменная в вашем /etc/fail2ban/filter.d/sshd.conf.

Бег с fail2ban-regex дал мне эти результаты, подтверждающие соответствие правилу:

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)
[...]