High Number Of Connection Attempts

[Pete]

Hello,






[..]



[..]

The full log file can be found here :

http://nrth.org/abuse/2012-02-04-opal_solutions-talktalk-smtp-auth.txt

I've grep'd 938 instances of the next line :





Thanks for your time.

Regards,

Pete.

Can someone confirm that the log excerpt below is most likely a bot of some kind attempting to authenticate to my Postfix server please ? Seems like I could do with slowing such attempts down. Any advice on best practices would be welcome. Feb 4 15:00:23 tooms postfix/smtpd[89297]: warning: 213.83.78.219: hostname bri209-79623-rtr-adsl-219.altohiway.com verification failed: hostname nor servname provided, or not known Feb 4 15:00:23 tooms postfix/smtpd[89298]: warning: 213.83.78.219: hostname bri209-79623-rtr-adsl-219.altohiway.com verification failed: hostname nor servname provided, or not known Feb 4 15:00:24 tooms postfix/smtpd[89288]: lost connection after AUTH from unknown[213.83.78.219] Feb 4 15:00:24 tooms postfix/smtpd[89286]: lost connection after AUTH from unknown[213.83.78.219] Feb 4 15:00:24 tooms postfix/smtpd[89289]: lost connection after AUTH from unknown[213.83.78.219] Feb 4 15:00:24 tooms postfix/smtpd[89290]: lost connection after AUTH from unknown[213.83.78.219] Feb 4 15:00:32 tooms postfix/smtpd[89288]: lost connection after AUTH from unknown[213.83.78.219] This was between 15:00 and 15:08 today. 'altohiway.com' is now blocked for the time being.

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