Prerequisite

Resolving MailScanner Dependencies

  1. Run the following cpan commands one at a time (i.e. to see if they are successfully installed): 
    sudo cpan -i Filesys::Df
    sudo cpan -i IO::Stringy
    sudo cpan -i DBI
    sudo cpan -i Net::CID
    sudo cpan -i Sys::SigAction
    sudo cpan -i MIME::Parser
    sudo cpan -i Archive::Zip
    sudo cpan -i OLE::Storage_Lite
    sudo cpan -i DBD::SQLite
  2. Install the following packages: 
    sudo apt-get install unrar
sudo apt-get install sqlite

Installing Clamav Antivirus

Run the following command:

sudo apt-get install clamav clamav-daemon

Integrating Clamav to MailScanner

  1. Update the /etc/MailScanner/MailScanner.conf to have the fields Virus Scanner and Clamd Socket to become as follows: 
    Virus Scanner = clamd
Clamd Socket = /var/run/clamav/clamd.ctl
  2. Restart the mailscanner service with the following command: 
    sudo service mailscanner restart
  3. Update the file /etc/apparmor.d/usr.sbin.clamd to have the following entries: 
      /var/spool/MailScanner/** rw,
  /var/spool/MailScanner/incoming/** rw,
  4. Restart the apparmor service with the following command: 
    sudo systemctl restart apparmor.service

Installing and Updating Spamassassin

Run the following commands:

sudo apt-get install spamassassin
sudo sa-update
sudo service spamassassin start

Integrating MailScanner to Postfix

  1. Open the file /etc/postfix/main.cf for editing and add the following line and save: 
    header_checks = regexp:/etc/postfix/header_checks
  2. Create the file /etc/postfix/header_checks with the following: 
    /^Received:/ HOLD
  3. Open the file /etc/MailScanner/MailScanner.conf for editing and update with the following if necessary: 
    Run As User = postfix
Run As Group = postfix
Incoming Queue Dir = /var/spool/postfix/hold
Outgoing Queue Dir = /var/spool/postfix/incoming
MTA = postfix
  4. Open the file /etc/MailScanner/defaults for editing and update with the following if necessary: 
    run_mailscanner=1
  5. Update the group of /var/spool/MailScanner to mtagroup and allow the it write permission as follows: 
    sudo chown :mtagroup /var/spool/MailScanner
sudo chmod 775 MailScanner
  6. Prepare spamassassin's directory using the following commands: 
    sudo mkdir /var/spool/MailScanner/spamassassin
sudo chown postfix /var/spool/MailScanner/spamassassin
  7. Update the permission of the MailScanner's incoming and quarantine folders with the following commands: 
    sudo chown postfix.mtagroup /var/spool/MailScanner/incoming
sudo chmod 770 /var/spool/MailScanner/incoming
sudo chown postfix.mtagroup /var/spool/MailScanner/quarantine
  8. Restart the mailscanner service with the following command: 
    sudo service mailscanner restart

Related Post
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