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On 30/11/2007, Arturo 'Buanzo' Busleiman <buanzo@××××××××××.ar> wrote: |
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> Hash: SHA512 |
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> |
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> Randy Barlow wrote: |
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> > I am getting a huge number of connections to my mail server (postfix) |
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> > compared to usual. I've seen as many as 50 connections open at one |
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> > time. The logs show that the connections are from several computers of |
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> > varying IPs, and they are all trying to send mail to random mailboxes on |
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> > my domain. It's very annoying, and I have noticed that inbound mail |
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> > seems to be lagging by several hours. Is there something similar to |
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> > denyhosts for spammers? Any other suggestions? |
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> |
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> Check those IPs against: www.robtex.com/rbl |
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> Choose your favorite blacklists (test them, some of them provide too many false positives) and |
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> implement with them DNSBL/RBL in your postfix. Also, SPF and greylisting make a good job. |
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Regarding SPF, I'd just like to add that the SPF policy daemons (which |
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can be integrated into postfix very easily) are available at |
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http://www.openspf.org/Software. There are implementations in perl and |
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python and, as luck would have it, the python version is available in |
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portage as mail-filter/pypolicyd-spf. If you choose to endorse SPF |
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then don't forget to define records for one's own domains! A helpful |
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document describing SPF syntax can be found here: |
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http://www.openspf.org/SPF_Record_Syntax. |
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Regards, |
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|
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--Kerin |
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-- |
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