Normally, I can send email from commandline, such as
echo hello | mail -s "subject" [email protected]
I have noticed that even when Postfix is not running on my machine, I can still "send" emails. Actually they are being queued in /var/spool/postfix/maildrop
. But once Postfix is started again, these emails will be sent out.
Can somebody please explain how this works? Who copies the emails into /var/spool/postfix/maildrop
, is it the email client (heirloom
in my case) ?
Does it mean, I have a guarantee all emails will be always delivered, regardless whether Postfix is running or not?