>> I think the "barrier to entry" is too difficult for most. I would >> have to setup a new MX on a domain without MTA checks (DNS and RBL)
I set this up and it was much easier than I had thought. The wiki documentation was helpful but very confusing at first. Start with: https://wiki.apache.org/spamassassin/NightlyMassCheck The automasscheck-minimal.sh does all of the work pulling down the latest rules, running the masscheck, then uploading the results (not your email) to the rulesQA server. I setup an iRedMail server leaving the default Postfix MTA postscreen settings to do basic DNS and RBL checks which uses zen.spamhaus.org and b.barracudacentral.org. The default iRedmail spam filtering works pretty well so I would recommend anyone interested take a look at it. NOTE: I disabled all RBLs and DNS checks and saw way too much spam to even start sorting through so I enabled it again. I did disable greylisting done by the iredapd service to allow more spam in. Here are my install notes: - Create new VM and install iRedmail Pick a domain that doesn't matter or conflict with real mail flow Setup a catchall address to direct mail to the postmaster mailbox. Don't worry about DNS PTR, SPF, and DKIM since this server will not be sending outbound - Run sa-update to get the rules in place without waiting on cron - Disable the iredapd daemon doing greylisting and content filtering /etc/postfix/main.cf Comment lines with '7777' systemctl stop iredapd.service systemctl disable iredapd.service - v320.pre: loadplugin Mail::SpamAssassin::Plugin::Shortcircuit - v310.pre: loadplugin Mail::SpamAssassin::Plugin::DCC Install DCC - Install Pyzor - Change amavisd-new to always add X-Spam-Status tag with rule details /etc/amavisd/amavisd.conf $sa_tag_level_deflt = -999; - Setup MX record and A record pointing to the iRedMail server - If you don't start seeing mail immediately, test mail flow from the Internet using Wormly SMTP test - I setup rules to help sort the mail into folders before I manually sort them into the Ham and Spam folders - Continue with step 4 from: https://wiki.apache.org/spamassassin/NightlyMassCheck I used the vmail user with home dir /var/vmail. /var/vmail/bin/automasscheck-minimal.sh /var/vmail/.auto-mass-check.cf - wiki step 6 needs to be corrected or the script updated with correct filename MAILDIR="/var/vmail/vmail1/[domain]/p/o/s/postmaster-[date]/Maildir" Line 52: run_masscheck single-corpus \ ham:dir:$MAILDIR/.Ham/ \ spam:dir:$MAILDIR/.Spam/ - Put a few ham and spam into their folder in iRedMail Roundcube web interface and test the automasscheck-minimal.sh script without the rsync creds to get familiar with the process and check your ham.log and spam.log - I added the following lines to the automasscheck-minimal.sh to allow easy running of the hit-frequency script: (line 95 - end of run_masscheck function) ln -s ham-${LOGNAME}.log ham.log ln -s spam-${LOGNAME}.log spam.log - Check out the tools like hit-frequency for interesting info: (as user vmail) ~/masscheckwork/nightly_mass_check/masses Hope this helps get more people involved in the masschecking. If I have accidentally missed something above, please correct. Dave