tag:blogger.com,1999:blog-14311740.post-2498886111127626722008-03-18T15:38:00.000-07:002008-03-18T16:06:38.928-07:00<a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://bp1.blogger.com/_h6vxr1Bf3cw/R-BK3ZiiLxI/AAAAAAAAAhU/HThBWc6PJX0/s1600-h/spam.jpg"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer;" src="http://bp1.blogger.com/_h6vxr1Bf3cw/R-BK3ZiiLxI/AAAAAAAAAhU/HThBWc6PJX0/s320/spam.jpg" alt="" id="BLOGGER_PHOTO_ID_5179221887085063954" border="0" /></a>In <a href="http://c600g.blogspot.com/2007/11/war-on-spam.html">this old post</a>, I spilled the beans on my new and improved spam filtering triple play: <a href="http://dspam.nuclearelephant.com/">dspam</a>, <a href="http://www.jonatkins.com/page/software/qgreylist">qgreylist</a> and <a href="http://en.wikipedia.org/wiki/DNSBL">RBL</a> checking. Overall, the system has worked well over the last four months, though I have noticed the increasing volume of spam showing up in my spam folder.<br /><br />I suspected that the very simple form of <a href="http://en.wikipedia.org/wiki/Greylisting">greylisting</a> implemented in qgreylist was the culprit, and after a bit of investigation, I found out that this indeed was the case. So, I set out to see if there was another greylisting implementation which could be used in my <a href="http://qmail.org/top.html">qmail</a> installation.<br /><br />Using my google-fu, I quickly zeroed in on <a href="http://mij.oltrelinux.com/net/greylite/">Greylite</a>. After reading up on it, I found that it held several advantages over qgreylist:<br /><ol><li>Written in C instead of perl, so it should perform a bit snappier and be less of a burden on the mail server.</li><li>Instead of only considering the IP address of the sender as qgreylist does, greylite considers the complete triplet of {IP address, from, to} before validating an IP address.</li><li>All data is stored in a single sqlite3 database, whereas qgreylist stored the verified IP addresses as files in a single directory, which clutters the filesystem and increases access time in that directory as more IPs are validated.</li><li>Greylite appears to have some enhanced functionality called `tuning suspicion' which allows you to customize how it behaves in certain circumstances.</li></ol><a onblur="try {parent.deselectBloggerImageGracefully();} catch(e) {}" href="http://bp0.blogger.com/_h6vxr1Bf3cw/R-BJ_JiiLwI/AAAAAAAAAg0/UJc2x7mKMcM/s1600-h/flawless_victory.png"><img style="margin: 0pt 0pt 10px 10px; float: right; cursor: pointer;" src="http://bp0.blogger.com/_h6vxr1Bf3cw/R-BJ_JiiLwI/AAAAAAAAAg0/UJc2x7mKMcM/s400/flawless_victory.png" alt="" id="BLOGGER_PHOTO_ID_5179220920717422338" border="0" /></a>To install it on my debian box, I first had to install sqlite3 (and the associated development libraries). Then, I downloaded the source code and followed the simple directions that came with it.<br /><br />Less than 5 mintues later, and the server was up and running with its new greylisting implementation up and working perfectly. Flawless victory!Alanhttp://www.blogger.com/profile/00999861302655014098noreply@blogger.com