Your welcome.

On Wed, 2015-09-30 at 10:29 -0700, Gao wrote:
> Thnaks. Added the maxlines and now looks good:
> 
> 
> [root@szeta ~]#
> fail2ban-regex  /var/log/maillog-20150928 
> /etc/fail2ban/filter.d/postfix-auth.conf
> 
> Running tests
> =============
> 
> Use   failregex filter file : postfix-auth, basedir: /etc/fail2ban
> Use         maxlines : 10
> Use         log file : /var/log/maillog-20150928
> Use         encoding : UTF-8
> 
> 
> Results
> =======
> 
> Failregex: 311 total
> |-  #) [# of hits] regular expression
> |   1) [260] ^\s*(<[^.]+\.[^.]+>)?\s*(?:\S+ )?(?:kernel: \[ *\d+\.\d
> +\] )?(?:@vserver_\S+ )?(?:(?:\[\d+\])?:\s
> +[\[\(]?postfix/(submission/)?smtp(d|s)(?:\(\S
> +\))?[\]\)]?:?|[\[\(]?postfix/(submission/)?smtp(d|s)(?:\(\S
> +\))?[\]\)]?:?(?:\[\d+\])?:?)?\s(?:\[ID \d+ \S+\])?\s*lost connection
> after AUTH from (.*)\[<HOST>\]
> |   2) [49] ^\s*(<[^.]+\.[^.]+>)?\s*(?:\S+ )?(?:kernel: \[ *\d+\.\d+\]
> )?(?:@vserver_\S+ )?(?:(?:\[\d+\])?:\s
> +[\[\(]?postfix/(submission/)?smtp(d|s)(?:\(\S
> +\))?[\]\)]?:?|[\[\(]?postfix/(submission/)?smtp(d|s)(?:\(\S
> +\))?[\]\)]?:?(?:\[\d+\])?:?)?\s(?:\[ID \d+ \S+\])?\s*lost connection
> after EHLO from (.*)\[<HOST>\]
> |   3) [2] ^\s*(<[^.]+\.[^.]+>)?\s*(?:\S+ )?(?:kernel: \[ *\d+\.\d+\]
> )?(?:@vserver_\S+ )?(?:(?:\[\d+\])?:\s
> +[\[\(]?postfix/(submission/)?smtp(d|s)(?:\(\S
> +\))?[\]\)]?:?|[\[\(]?postfix/(submission/)?smtp(d|s)(?:\(\S
> +\))?[\]\)]?:?(?:\[\d+\])?:?)?\s(?:\[ID \d+ \S+\])?\s*lost connection
> after UNKNOWN from (.*)\[<HOST>\]
> `-
> 
> Ignoreregex: 0 total
> 
> Date template hits:
> |- [# of hits] date format
> |  [10623] (?:DAY )?MON Day 24hour:Minute:Second(?:\.Microseconds)?(?:
> Year)?
> `-
> 
> Lines: 10623 lines, 0 ignored, 311 matched, 10312 missed [processed in
> 1.44 sec]
> Missed line(s): too many to print.  Use --print-all-missed to print
> all 10312 lines
> 
> 
> 
> 
> On 15-09-30 10:05 AM, Harrison Johnson wrote:
> 
> > 
> > In the [Init] section of the filter file add a line:
> >     maxlines = 10
> > this sets up a buffer of 10 lines from the log file change the
> > number as needed. Now your failregex will match to those lines.
> > On Wed, 2015-09-30 at 09:14 -0700, Gao wrote: 
> > 
> > > After another look of the maillog, I see there are also at least another 
> > > attack like this, instead of AUTH, there are EHLO, RCPT, UNKNOWN, 
> > > STARTTLS and CONNECT, among these, EHLO is for sure anther attack. The 
> > > others does not have many attempts in a short period.
> > > 
> > > May be I should make it a wildcard in the filter. But I don't want block 
> > > the normal user by mistake.
> > > 
> > > Now, I set findtime=120 and maxretry=5. Also the filter now is like this:
> > > 
> > > failregex = ^%(__prefix_line)slost connection after AUTH from 
> > > (.*)\[<HOST>\]
> > >              ^%(__prefix_line)slost connection after EHLO from 
> > > (.*)\[<HOST>\]
> > >              ^%(__prefix_line)slost connection after UNKNOWN from 
> > > (.*)\[<HOST>\]
> > > 
> > > 
> > > Gao
> > > 
> > > 
> > > 
> > > 
> > > 
> > > 
> > > On 15-09-30 04:42 AM, Nick Howitt wrote:
> > > > I think it can be pretty bad behaviour if you get too many attempts too
> > > > quickly. I've seen over 1000 in 24h from a single IP. I generally see
> > > > nothing but every now and then someone has a go and it is a bit
> > > > irritating.
> > > >
> > > > I also had one IP doing about 6 attempts an hour for days until I
> > > > spotted it and blocked it. I was blocking 10 occurrences in an hour but
> > > > dropped it to 5 an hour to combat the IP.
> > > >
> > > > On 2015-09-30 12:08, Darac Marjal wrote:
> > > >> On Tue, Sep 29, 2015 at 02:30:47PM -0700, Gao wrote:
> > > >>> Hello, all
> > > >>>
> > > >>> I have the postfix-sasl jail enabled and it works well against attack,
> > > >>> such as
> > > >>> "Failed login".
> > > >>>
> > > >>> I just notified that my email server's maillog flood with this:
> > > >>> ...
> > > >>> Sep 29 14:19:21 szeta postfix/smtpd[19940]: connect from
> > > >>> ns3366447.ip-37-187-77.eu[37.187.77.147]
> > > >>> Sep 29 14:19:22 szeta postfix/smtpd[19940]: lost connection after AUTH
> > > >>> from
> > > >>> ns3366447.ip-37-187-77.eu[37.187.77.147]
> > > >>> Sep 29 14:19:22 szeta postfix/smtpd[19940]: disconnect from
> > > >>> ns3366447.ip-37-187-77.eu[37.187.77.147]
> > > >> "Lost connection after AUTH" means that postfix sent "AUTH" to the
> > > >> client, and the client disconnected. In other words, the client
> > > >> probably
> > > >> attempted some action which you've configured that only authorized
> > > >> users
> > > >> can perform (usually, this is something like sending mail to a
> > > >> different
> > > >> serveer (relaying)). Postfix said "authorize yourself in order to
> > > >> perform this action", and the client just dropped the connection
> > > >> (rather
> > > >> than cleanly quitting and waiting for postfix to close the conecction).
> > > >>
> > > >> In other words, no authorization was attempted.
> > > >>
> > > >> I suspect that fail2ban doesn't block this normally because it's not
> > > >> really bad behaviour. It's akin to someone connecting to your SSH port
> > > >> and disconnecting upon finding that it's asking for a password :)
> > > >>
> > > >>> ...
> > > >>>
> > > >>> And the fail2ban does nothing about this! No new entry about this in
> > > >>> fail2ban.log. The attack is still going and I am going to manual kill
> > > >>> it in
> > > >>> iptables.
> > > >>>
> > > >>> What should I do about this in fail2ban? Please help.
> > > >>>
> > > >>> Thanks.
> > > >>>
> > > >>> Gao
> > > >>>
> > > >>> ------------------------------------------------------------------------------
> > > >>> _______________________________________________
> > > >>> Fail2ban-users mailing list
> > > >>> [email protected]
> > > >>> https://lists.sourceforge.net/lists/listinfo/fail2ban-users
> > > >>
> > > >> ------------------------------------------------------------------------------
> > > >>
> > > >> _______________________________________________
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> > > >> [email protected]
> > > >> https://lists.sourceforge.net/lists/listinfo/fail2ban-users
> > > > ------------------------------------------------------------------------------
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> > > > [email protected]
> > > > https://lists.sourceforge.net/lists/listinfo/fail2ban-users
> > > 
> > > 
> > > ------------------------------------------------------------------------------
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> > > [email protected]
> > > https://lists.sourceforge.net/lists/listinfo/fail2ban-users
> > 
> > 
> 
> 


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