vegetaaaaaaa , 2 months ago (edited 2 months ago)

You can definitely replace senders with correct mail addresses for relaying through SMTP servers that expect them (this is what I do):

# /etc/msmtprc
account default
...
host smtp.gmail.com
auto_from on
auth on
user myaddress
password hunter2

# Replace local recipients with addresses in the aliases file
aliases /etc/aliases

# /etc/aliases
mailer-daemon: postmaster
postmaster: root
nobody: root
hostmaster: root
usenet: root
news: root
webmaster: root
www: root
ftp: root
abuse: root
noc: root
security: root
root: default
www-data: root
default: myaddress@gmail.com

(the only thing I changed from the defaults in the aliases file is adding the last line)

This makes it so all/most system accounts susceptible to send mail are aliased to root, and root in turn is aliased to my email address (which is the one configured in host/user/password in msmtprc)

Edit: I think it's actually the auto_from option which interests you. Check the msmtp manpage