Raspberry Pi & Arch Linux - Day 3

Raspberry Pi & Arch Linux - Day 3

In this brief post, we will describe how to send email in Arch. 

There are several choices to send email in linux. To get things done quickly, I choose the one that looks the simplest: SSMTP.

Problem 3: How to send an email with SSMTP

If the ssmtp tool is not installed on the system, type pacman -S package-name to install it. On my Arch Linux, the ssmtp is not pre-installed.

After the installation, we need to edit the configuration file in /etc/ssmtp/ssmtp.conf. The configuration is straightforward and the options are self-explanatory.

Here is the sample configuration file copied from the Arch Wiki:

/etc/ssmtp/ssmtp.conf

# The user that gets all the mails (UID < 1000, usually the admin)
root=username@gmail.com

# The mail server (where the mail is sent to), both port 465 or 587 should be acceptable
# See also https://support.google.com/mail/answer/78799
mailhub=smtp.gmail.com:587

# The address where the mail appears to come from for user authentication.
rewriteDomain=gmail.com

# The full hostname
hostname=localhost

# Use SSL/TLS before starting negotiation
UseTLS=Yes
UseSTARTTLS=Yes

# Username/Password
AuthUser=username
AuthPass=password

# Email 'From header's can override the default domain?
FromLineOverride=yes

To send an email, use the following command:

$ echo test | mail -v -s "testing ssmtp setup" tousername@somedomain.com

There is one critical issue with this approach: the security.  Note that the configuration contains the email username and password. It is not safe to keep your personal profile in this way. The Arch Wiki page suggests creating a new ssmtp group and set the ownership. The security problem would be my next topic but for today at least we can send the email.

Trick

As a beginner to the linux system, I am not familiar with all the commands. I often store some commands in a text file. Some commands are really long and it is not convenient to type the code every time. Here is a command that select a specific line in the file and execute it.

$ cat my-command-file | awk "NR==line-of-interest{print}" | bash

The first part of the command is just to print out the whole file; the second part is to select the line of interest and then finally pass it to bash. The bash command will execute the string command coming out of awk tool.