Command Line Email

Beginner Linux Fundamentals
mailmailxmuttsendmail

Objective

Send and receive email from the Linux command line using mail/mailx utilities, and understand how local and remote mail delivery works.

Tools & Technologies

  • mail
  • mailx
  • mutt
  • sendmail

Key Commands

echo 'body' | mail -s 'Subject' user@host
mail -s 'test' admin@localhost < report.txt
mailx -r from@domain -s 'subj' to@domain

Architecture Overview

sequenceDiagram participant U as User (CLI) participant M as MTA (Postfix/sendmail) participant Q as Mail Queue participant R as Recipient MTA participant MB as Mailbox U->>M: mail -s 'subject' user@host M->>Q: Queue message Q->>R: SMTP delivery R->>MB: Store in mailbox Note over U,MB: Local mail goes directly to /var/spool/mail/

Step-by-Step Process

01
Send Basic Email

Use the mail command to send a message from the command line.

# Simple one-liner
echo 'This is the body' | mail -s 'Test Subject' user@localhost

# From a file
mail -s 'Monthly Report' [email protected] < report.txt

# Multiple recipients
echo 'See attached' | mail -s 'FYI' alice@host bob@host
02
Read Mail

The mail command is also an interactive mail reader.

mail          # open mailbox
# Interactive commands:
p             # print/read message
d             # delete message
r             # reply
q             # quit
h             # list headers
03
Check Mail Queue & Logs

Monitor mail delivery status and troubleshoot delivery failures.

# View mail queue
mailq
# Force queue flush
sudo sendmail -q
# Check mail log
sudo tail -f /var/log/mail.log
sudo journalctl -u postfix

Challenges & Solutions

  • Local mail goes to /var/spool/mail/username — check if MTA is running
  • External mail requires properly configured DNS MX records and may be blocked by ISP

Key Takeaways

  • mail command doubles as both sender and reader
  • mutt and neomutt are far more capable TUI mail clients for daily use