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From: Nikolai Georgiev <voyager123bg@gmail.com>
To: Dave Handler <dhandler@nycap.rr.com>
Cc: netfilter@lists.netfilter.org
Subject: Re: How to drop an isp
Date: Sat, 05 Nov 2005 20:41:26 +0200	[thread overview]
Message-ID: <436CFCD6.7070206@gmail.com> (raw)
In-Reply-To: <436CBBFB.1070101@nycap.rr.com>

Dave Handler wrote:

> Greetings!
>
> Sorry if I worded my subject wrong, it's the best I could do!
>
> Ok, I'm on Fedora Core 3, running iptables 1.2 (which seems to be
> holding its own).  Logwatch sends me my logs every morning and I see
> people trying to tap in to tcp port 25.  I do lookups on the addresses
> and they all seems to be coming either from Taiwan or China.  A few in
> Europe and every once in while one from the US.
>
> I've been googling around for how to block them.  I'm rather green to
> iptables and some of the options confuse me.  Is there a way I can
> block the whole ip from me?  I'll paste in a section where there where
> accepted packets:
>
> Accepted 327 packets on interface eth0
>  From 69.21.138.231 - 169 packets to tcp(22)
>  From 70.86.208.18 - 6 packets to tcp(25)
>  From 72.36.128.42 - 6 packets to tcp(25)
>  From 202.107.195.52 - 128 packets to tcp(22)
>  From 207.150.176.81 - 16 packets to tcp(25)
>  From 219.133.247.226 - 1 packet to tcp(25)
>  From 219.134.232.31 - 1 packet to tcp(25)
>
>
> So for instance I probably would want to block 202.107.0.0 through
> 202.107.255.255.  But I'm not really sure of the syntax I should be
> using.  And I don't want to screw up what I already have in place.
>
iptables -I INPUT --src 202.107/16 --p tcp --dport 25 -j DENY

> I'm going to chalk this one up as another learning experience!
>
> Thanks in advance!
>
> Dave
>
>



  reply	other threads:[~2005-11-05 18:41 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2005-11-05 14:04 How to drop an isp Dave Handler
2005-11-05 18:41 ` Nikolai Georgiev [this message]
2005-11-05 21:49 ` Robert Nichols

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