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content/blog/send-mails-openwrt-msmtp-gmail.md

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+---
+title: "Send mails on OpenWRT with MSMTP and Gmail"
+date: 2020-04-08T00:00:00+02:00
+opensource:
+- OpenWRT
+---
+
+A previous article named "[Install OpenWRT on your Raspberry PI](../install-openwrt-raspberry-pi/)" goes through the setup process to use OpenWRT on your Raspberry PI.
+As a consequence, you might now have a Raspberry PI running OpenWRT and full of services of which all your family relies on.
+With great power comes great responsibilities.
+So, you might want to be notified when something goes wrong, a cron job failed, a hard disk is dying, etc., so that you can fix the problem at earliest, maybe before anyone else could notice.
+
+This article explains how to send mails on OpenWRT with MSMTP and a GMail account.
+You can adapt this procedure to any email provider that supports SMTP access with a login and password.
+
+## Configure GMail
+
+How to configure GMail to allow SMTP access depends on the security settings of your account.
+
+* If you have two-factor authentication (2FA) enabled, you will need to create an [app password](https://myaccount.google.com/apppasswords). Google will generate a strong password for you.
+* If you do **NOT** have 2FA enabled, you will need to allow access to unsecured apps from the [Less Secure Apps](https://myaccount.google.com/lesssecureapps) page.
+
+## Install MSMTP
+
+On your OpenWRT device, install the msmtp package.
+
+```sh
+opkg update
+opkg install msmtp
+```
+
+Create the MSMTP configuration file **/etc/msmtprc**.
+
+```
+# A system wide configuration file is optional.
+# If it exists, it usually defines a default account.
+# This allows msmtp to be used like /usr/sbin/sendmail.
+account default
+
+# The place where the mail goes. The actual machine name is required
+# no MX records are consulted. Both port 465 or 587 should be acceptable
+# See also https://support.google.com/mail/answer/78799
+host smtp.gmail.com
+port 587
+
+# Construct envelope-from addresses of the form "user@oursite.example".
+# auto_from on
+# maildomain itix.fr
+auto_from off
+from change.me@gmail.com
+
+# Dispatch mails according to /etc/aliases
+aliases /etc/aliases
+
+# Use TLS.
+tls on
+tls_starttls on
+tls_trust_file /etc/ssl/certs/ca-certificates.crt
+
+# Syslog logging with facility LOG_MAIL instead of the default LOG_USER.
+syslog LOG_MAIL
+
+# Authenticate to GMail
+#
+# If your Gmail account is secured with two-factor authentication, you need
+# to generate a unique App Password to use in ssmtp.conf.
+# See https://support.google.com/mail/answer/185833
+# App Passwords can be generated on https://myaccount.google.com/apppasswords
+#
+# Use you Gmail username (not the App Name) in the AuthUser line and use the
+# generated 16-character password in the AuthPass line, spaces in the password
+# can be omitted.
+#
+# If you do not use two-factor authentication, you need to allow access to
+# unsecure apps. You can do so on your Less Secure Apps page.
+# See https://support.google.com/accounts/answer/6010255
+# You can do so on https://myaccount.google.com/lesssecureapps
+
+auth on
+user change.me@gmail.com
+password changeme
+```
+
+Create the **/etc/aliases** file so that every mail sent to a local user (root, ftp, nobody, etc.) is in fact sent to the designated email address.
+This is a safe measure in order no to lose emails.
+
+```
+default: change.me@gmail.com
+```
+
+Of course, do not forget to replace the email address (**change.me@gmail.com**) and password (**changeme**) with the actual values in both files.
+
+If you know **for sure** that all the mails will be sent by root or daemons running as root, you can tighten up the file permissions. Otherwise, let it as-is.
+
+```sh
+chmod 600 /etc/msmtprc
+```
+
+You can make **msmtp** be an alias for the **sendmail** that most unix daemons are looking for.
+
+```sh
+ln -s /usr/bin/msmtp /usr/sbin/sendmail
+```
+
+## Run a test
+
+The following command sends a mail to the **root** user.
+If you configured **/etc/aliases** as instructed with a fallback on your email address, you should receive a mail containing the famous "Hello, World!".
+
+```sh
+echo -e "Subject: Hello!\n\nHello, world!" |sendmail root
+```
+
+## Daemon configuration
+
+The cron daemon from OpenWRT is based on busybox and has **NOT** be compiled with the option to send emails.
+So if you want to be notified when a cron fails, you will have to recompile busybox with "**Report command output via email (using sendmail)**" enabled.
+The article named "[Nginx with TLS on OpenWRT](../nginx-with-tls-on-openwrt/)" explains how to recompile a package with a different configuration and how to install it.
+
+## Conclusion
+
+This article explained how to send mails on OpenWRT with MSMTP and a GMail account.