ubuntu – 为什么fail2ban发现但不禁止

我在Ubuntu Xenial服务器上发现了一些奇怪的东西.
它在默认端口上有SSH,它有fail2ban.
Fail2ban正在检测服务器上的强力尝试并相应地记录：

2017-01-12 10:58:19,927 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:03:27,808 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:08:37,936 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:13:51,538 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:18:57,939 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:24:10,399 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:29:23,161 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:34:34,064 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x
2017-01-12 11:39:44,540 fail2ban.filter    [23119]: INFO    [sshd] Found x.x.x.x

x.x.x.x在所有实例中都是相同的IP,这个人只是网络钓鱼随机用户名,如auth.log中所示：

Jan 12 12:05:46 MYSERVER sshd[23579]: Invalid user journalist from x.x.x.x
Jan 12 12:05:46 MYSERVER sshd[23579]: input_userauth_request: invalid user journalist [preauth]
Jan 12 12:05:46 MYSERVER sshd[23579]: Received disconnect from x.x.x.x port 47995:11: normal Shutdown,Thank you for playing [preauth]
Jan 12 12:05:46 MYSERVER sshd[23579]: disconnected from x.x.x.x port 47995 [preauth]

Fail2ban看到了他们,他把它们列为“发现”,但没有禁止.有任何想法吗？

编辑：

cat /etc/fail2ban/jail.d/myjails.local
[apache-auth]
enabled = true

[sshd-ddos]
enabled = true

[recidive]
enabled = true

[dovecot]
enabled = true

[postfix]
enabled=true

其余的配置文件保留原样,根据Ubuntu的默认设置,即/etc/fail2ban/jail.conf具有：

[sshd]

port    = ssh
logpath = %(sshd_log)s


[sshd-ddos]
# This jail corresponds to the standard configuration in Fail2ban.
# The mail-whois action send a notification e-mail with a whois request
# in the body.
port    = ssh
logpath = %(sshd_log)s

我们有：

cat /etc/fail2ban/jail.d/defaults-debian.conf
[sshd]
enabled = true

[DEFAULT]
findtime = 3600
bantime = 3600
maxretry = 4