Fail2ban - postfix/smtpd

I am not sure if my set up does not work, or this is normal, but looking at the
tail -f /var/log/mail.log

I get a lot of:

Oct 18 14:53:47 box postfix/smtpd[12848]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:53:47 box postfix/smtpd[12848]: disconnect from unknown[210.65.114.3]
Oct 18 14:53:49 box postfix/smtpd[12311]: connect from unknown[210.65.114.3]
Oct 18 14:53:50 box postfix/smtpd[12311]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:53:50 box postfix/smtpd[12311]: disconnect from unknown[210.65.114.3]
Oct 18 14:53:53 box postfix/smtpd[12310]: connect from unknown[210.65.114.3]
Oct 18 14:53:54 box postfix/smtpd[12310]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:53:54 box postfix/smtpd[12310]: disconnect from unknown[210.65.114.3]
Oct 18 14:53:56 box postfix/smtpd[12848]: connect from unknown[210.65.114.3]
Oct 18 14:53:57 box postfix/smtpd[12848]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:53:57 box postfix/smtpd[12848]: disconnect from unknown[210.65.114.3]
Oct 18 14:53:58 box postfix/smtpd[12310]: connect from unknown[210.65.114.3]
Oct 18 14:53:59 box postfix/smtpd[12310]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:53:59 box postfix/smtpd[12310]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:00 box postfix/smtpd[12311]: connect from unknown[210.65.114.3]
Oct 18 14:54:01 box postfix/smtpd[12311]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:01 box postfix/smtpd[12311]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:05 box postfix/smtpd[12848]: connect from unknown[210.65.114.3]
Oct 18 14:54:06 box postfix/smtpd[12848]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:06 box postfix/smtpd[12848]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:09 box postfix/smtpd[12311]: connect from unknown[210.65.114.3]
Oct 18 14:54:10 box postfix/smtpd[12311]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:10 box postfix/smtpd[12311]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:12 box postfix/smtpd[12310]: connect from unknown[210.65.114.3]
Oct 18 14:54:13 box postfix/smtpd[12310]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:13 box postfix/smtpd[12310]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:15 box postfix/smtpd[12848]: connect from unknown[210.65.114.3]
Oct 18 14:54:15 box postfix/smtpd[12848]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:15 box postfix/smtpd[12848]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:18 box postfix/smtpd[12311]: connect from unknown[210.65.114.3]
Oct 18 14:54:19 box postfix/smtpd[12311]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:19 box postfix/smtpd[12311]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:21 box postfix/smtpd[12310]: connect from unknown[210.65.114.3]
Oct 18 14:54:22 box postfix/smtpd[12310]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:22 box postfix/smtpd[12310]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:24 box postfix/smtpd[12848]: connect from unknown[210.65.114.3]
Oct 18 14:54:25 box postfix/smtpd[12848]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:25 box postfix/smtpd[12848]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:28 box postfix/smtpd[12311]: connect from unknown[210.65.114.3]
Oct 18 14:54:28 box postfix/smtpd[12311]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:28 box postfix/smtpd[12311]: disconnect from unknown[210.65.114.3]
Oct 18 14:54:33 box postfix/smtpd[12310]: connect from unknown[210.65.114.3]
Oct 18 14:54:34 box postfix/smtpd[12310]: lost connection after AUTH from unknown[210.65.114.3]
Oct 18 14:54:34 box postfix/smtpd[12310]: disconnect from unknown[210.65.114.3]

from all sorts of IP addresses, should they been stopped by fail2ban?

Same here. Fail2ban never gets in action.