MailScanner with Postfix

January 16, 2020 ron Leave a comment

Prerequisite

Installed MailScanner

Resolving MailScanner Dependencies

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

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

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
```
Restart the mailscanner service with the following command:
```
sudo service mailscanner restart
```

Update the file /etc/apparmor.d/usr.sbin.clamd to have the following entries:

  /var/spool/MailScanner/** rw,
  /var/spool/MailScanner/incoming/** rw,

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

Open the file /etc/postfix/main.cf for editing and add the following line and save:
```
header_checks = regexp:/etc/postfix/header_checks
```
Create the file /etc/postfix/header_checks with the following:
```
/^Received:/ HOLD
```

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

Open the file /etc/MailScanner/defaults for editing and update with the following if necessary:
```
run_mailscanner=1
```
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
```

Prepare spamassassin's directory using the following commands:

sudo mkdir /var/spool/MailScanner/spamassassin
sudo chown postfix /var/spool/MailScanner/spamassassin

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

Restart the mailscanner service with the following command:
```
sudo service mailscanner restart
```

Linux, Server, Ubuntu

Configuring Email Server with Postfix and Dovecot

January 15, 2020 ron Leave a comment

Prerequisite

privkey.pem file
fullchain.pem file

Installing Postfix

Run the following commands:

sudo apt-get update
sudo apt-get install postfix

Configuring Postfix

Run the following command:
```
sudo dpkg-reconfigure postfix
```
Configuration questions:
1. Select OK to proceed.
2. Choose Internet Site.
3. System Mail Name: <EMAIL_DOMAIN>
4. Other destinations for mail: <EMAIL_DOMAIN>, localhost.<EMAIL_DOMAIN>, localhost
5. Force synchronous updates on mail queue?: No
6. Local networks: 127.0.0.0/8 [::ffff:127.0.0.0]/104 [::1]/128
7. Use procmail for local delivery?: No
8. Mailbox size limit (bytes): 0
9. Local address extension character: +
10. Internet protocols to use: all
Feel free to answer the preceding questions based on your setup. Just replace the EMAIL_DOMAIN (i.e. example.com) with a valid value.
Create the following folder:
```
/etc/postfix/ssl
```
Copy the your privkey.pem and fullchain.pem to /etc/postfix/ssl.

Do additional configurations by executing the following commands:

sudo postconf -e 'smtpd_sasl_local_domain ='
sudo postconf -e 'smtpd_sasl_auth_enable = yes'
sudo postconf -e 'smtpd_sasl_security_options = noanonymous'
sudo postconf -e 'broken_sasl_auth_clients = yes'
sudo postconf -e 'smtpd_recipient_restrictions =  permit_sasl_authenticated,permit_mynetworks,reject_unauth_destination'
sudo postconf -e 'inet_interfaces = all'
sudo postconf -e 'smtp_tls_security_level = may'
sudo postconf -e 'smtpd_tls_security_level = may'
sudo postconf -e 'smtpd_tls_auth_only = no'
sudo postconf -e 'smtp_tls_note_starttls_offer = yes'
sudo postconf -e 'smtpd_tls_loglevel = 1'
sudo postconf -e 'smtpd_tls_received_header = yes'
sudo postconf -e 'smtpd_tls_session_cache_timeout = 3600s'
sudo postconf -e 'tls_random_source = dev:/dev/urandom'	
sudo postconf -e 'mua_client_restrictions = permit_sasl_authenticated,reject'
sudo postconf -e 'mua_helo_restrictions = permit_mynetworks, permit_sasl_authenticated'
sudo postconf -e 'mua_sender_restrictions = permit_sasl_authenticated'
sudo postconf -e 'smtpd_tls_key_file = /etc/postfix/ssl/privkey.pem'
sudo postconf -e 'smtpd_tls_cert_file = /etc/postfix/ssl/fullchain.pem'
sudo postconf -e 'myhostname = ronella.xyz'

Create or update the /etc/postfix/sasl/smtpd.conf with the following:
```
pwcheck_method: saslauthd
mech_list: plain login
```

In the /etc/postfix/master.cf file, uncomment the submission section and must be like the following entries:

submission inet n       -       y       -       -       smtpd
  -o syslog_name=postfix/submission
  -o smtpd_tls_security_level=encrypt
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_reject_unlisted_recipient=no
  -o smtpd_client_restrictions=$mua_client_restrictions
  -o smtpd_helo_restrictions=$mua_helo_restrictions
  -o smtpd_sender_restrictions=$mua_sender_restrictions
  -o smtpd_recipient_restrictions=
  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
  -o milter_macro_daemon_name=ORIGINATING

Also in the same file, uncomment the smtps section and must be like the following entries:

smtps     inet  n       -       y       -       -       smtpd
  -o syslog_name=postfix/smtps
  -o smtpd_tls_wrappermode=yes
  -o smtpd_sasl_auth_enable=yes
  -o smtpd_reject_unlisted_recipient=no
  -o smtpd_client_restrictions=$mua_client_restrictions
  -o smtpd_helo_restrictions=$mua_helo_restrictions
  -o smtpd_sender_restrictions=$mua_sender_restrictions
  -o smtpd_recipient_restrictions=
  -o smtpd_relay_restrictions=permit_sasl_authenticated,reject
  -o milter_macro_daemon_name=ORIGINATING

Update the owner and group of /var/spool/postfix directory to become postfix as follows:
```
sudo chown postfix:postfix /var/spool/postfix
```
Restart the postfix service with the following command:
```
sudo systemctl restart postfix
```

Installing SASL

Run the following command:

sudo apt-get install libsasl2-2 sasl2-bin libsasl2-modules

Configuring SASL

Open the /etc/default/saslauthd file for editing.
Search for START=no and change it like the following:
```
START=yes
```

Add the following entries just after preceding entry:

PWDIR="/var/spool/postfix/var/run/saslauthd"
PARAMS="-m ${PWDIR}"
PIDFILE="${PWDIR}/saslauthd.pid"

Search for OPTIONS="-c -m /var/run/saslauthd" and change it like the following:
```
OPTIONS="-c -m /var/spool/postfix/var/run/saslauthd"
```

Update the dpkg state using the following command:

sudo dpkg-statoverride --force --update --add root sasl 755 /var/spool/postfix/var/run/saslauthd

Create a symbolic link using the following command:
```
sudo ln -s /etc/default/saslauthd /etc/saslauthd
```
Restart the sasl service using the following command:
```
sudo service saslauthd restart
```

Installing Dovecot

Run the following command:

sudo apt-get install dovecot-core dovecot-imapd dovecot-pop3d

The default location of the mail directory is /var/mail.

Configuring Dovecot

Update the certificate location in the file /etc/dovecot/conf.d/10-ssl.conf to be as follows:
```
ssl_cert = </etc/postfix/ssl/fullchain.pem
ssl_key = </etc/postfix/ssl/privkey.pem
```
Restart the dovecot service using the following command:
```
sudo service dovecot restart
```

Tool, Windows

Writing an Image File to an SDCard using Win32DiskImager

January 15, 2020 ron Leave a comment

Insert your SDCard.
Startup your Win32DiskImager.
On the Image file field, specify the location of the image file.
On the Device field, select the drive letter of the inserted SDCard.
Click the Write button.
To continue, click the Yes button and wait until it's done.
Once completed, click the OK button.
Click the Exit button.

Tool, Windows

Creating an Image File of an SDCard using Win32DiskImager

January 15, 2020 ron Leave a comment

Insert your SDCard.
Startup your Win32DiskImager.
On the Image file field, specify the desired filename of the image.
On the Device field, select the drive letter of the inserted SDCard.
Click the Read button and wait until it's done.
Once completed, click the OK button.
Click the Exit button.

Tool, Ubuntu

Installing a Debian Package in Ubuntu

January 14, 2020 ron Leave a comment

Run the following command:
```
sudo dpkg -i <DEBIAN_PACKAGE>
```
Token Description

DEBIAN_PACKAGE A Debian package that normally has deb extension.
Fix the broken dependencies by running the following command:
```
sudo apt-get install -f
```

Linux

Basic Postfix Management

January 14, 2020 ron Leave a comment

Command	Description
postqueue -p	Display the queue
postcat -vq <QUEUE_ID>	View the content of the email
postsuper -d ALL	Remove all emails
postsuper -d <QUEUE_ID>	Remove a particular email
postqueue -i <QUEUE_ID>	Attempt to send one particular email

Token	Description
QUEUE_ID	Can be identified by displaying the queue.

Linux, Tool

Using Rsync to Sync a Local Directory to Another Local Directory

January 7, 2020 ron Leave a comment

Syntax

To sync some of your local directories to another local directory, you can use the following syntax:

rsync -av -L --delete <DIR1>[[ <DIR2>] <DIRn>] <DESTINATION_DIR>

Token	Description
DIR1, DIR2, DIRn	These are the local directories you've wanted to be synced. Only DIR1 is required and the rest are optional.
DESTINATION_DIR	The destination directory on the remote machine.

Example

rsync -av -L --delete /var/log/ /data/log/

Git

Useful Environment Variable for Git Troubleshooting

January 7, 2020 ron Leave a comment

Variable	Description	Possible Values
GIT_CURL_VERBOSE	Tells Git to emit all the messages generated by that library. This is similar to doing curl -v on the command line.	1
GIT_SSL_NO_VERIFY	Tells Git not to verify SSL certificates.	true
GIT_TRACE	Controls general traces	1, 2 or true
GIT_TRACE_PACKET	Enables packet-level tracing for network operations.	true

Ron and Ella Wiki Page

Monthly Archives: January 2020

MailScanner with Postfix

Prerequisite

Resolving MailScanner Dependencies

Installing Clamav Antivirus

Integrating Clamav to MailScanner

Installing and Updating Spamassassin

Integrating MailScanner to Postfix

Configuring Email Server with Postfix and Dovecot

Prerequisite

Installing Postfix

Configuring Postfix

Installing SASL

Configuring SASL

Installing Dovecot

Configuring Dovecot

Writing an Image File to an SDCard using Win32DiskImager

Creating an Image File of an SDCard using Win32DiskImager

Installing a Debian Package in Ubuntu

Basic Postfix Management

Using Rsync to Sync a Local Directory to Another Local Directory

Useful Environment Variable for Git Troubleshooting

Extremely Serious

Token	Description
DEBIAN_PACKAGE	A Debian package that normally has deb extension.