Sending Email - RMerl/asuswrt-merlin.ng GitHub Wiki
Note that the below manual usage is still possible but there has long since been an easier way to send emails from your router. amtm has a built in method to enter all email credentials and store these in a central and accessible place for other addons to use. Link to the amtm wiki
Multiple addons supported by amtm and many that are not use these credentials to send emails.
And now, below starts the original manual method.
Asuswrt-Merlin includes a cutdown version of sendmail which can be used to send mail from the router. Basic usage will look like this:
echo "This is a test email." | /usr/sbin/sendmail -S"smtp.yourisp.com" -f"[email protected]" [email protected]
You can send a more proper Email by writing the mail to a file, and then piping it to sendmail. The following example, if saved as a wan-start script, will make your router send you an Email whenever the WAN interface comes up, containing the WAN IP:
#!/bin/sh
SMTP="smtp.yourisp.com"
FROM="[email protected]"
FROMNAME="Your Router"
TO="[email protected]"
echo "Subject: WAN state notification" >/tmp/mail.txt
echo "From: \"$FROMNAME\"<$FROM>" >>/tmp/mail.txt
echo "Date: $(date -R)" >>/tmp/mail.txt
echo "I just got connected to the Interwebz." >>/tmp/mail.txt
echo "My new IP is: $(nvram get wan0_ipaddr)" >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "--- " >>/tmp/mail.txt
echo "Your friendly router." >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
cat /tmp/mail.txt | /usr/sbin/sendmail -S"$SMTP" -f"$FROM" $TO
rm /tmp/mail.txt
If your SMTP server requires authentication, you can pass them as additional arguments. To see the available options, just run "sendmail -h".
If you don't have a smtp email account from your ISP, MailJet's SMTP relay serice could be the solution, it offers 200 mails for free a day. MailJet is a European based company in France, Paris.
Now just fill your wan-start script with the following lines but don't forget to replace the according lines with the data of your SMTP relay server (e.g. MailJet) and the email address where to receive notifications.
#!/bin/sh
SMTP="in-v3.mailjet.com:587"
FROM="your-mailjet-fromaddress"
FROMNAME="ASUS ROUTER"
TO="your-email-address"
ntpclient -h pool.ntp.org -s &> /dev/null
sleep 5
echo "Subject: WAN state notification" >/tmp/mail.txt
echo "From: \"$FROMNAME\"<$FROM>" >>/tmp/mail.txt
echo "Date: $(date -R)" >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "I just got connected to the internet." >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "My WAN IP is: $(nvram get wan0_ipaddr)" >>/tmp/mail.txt
echo "Uptime is: $(uptime | cut -d ',' -f1 | sed 's/^.\{12\}//g')" >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "---- " >>/tmp/mail.txt
echo "Your friendly router." >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
cat /tmp/mail.txt | /usr/sbin/sendmail -S"$SMTP" -f"$FROM" $TO -au"your-MailJet-username" -ap"your-MailJet-password"
rm /tmp/mail.txt
It's possible to send emails even from Gmail account through openssl (thanks Nerre), first we need to download a trusted certificate
wget -c -O /jffs/configs/google_root.pem https://pki.goog/roots.pem --no-check-certificate
Now fill your wan-start script with the following text but don't forget to replace FROM, AUTH, PASS and TO values only in first six lines of the script
#!/bin/sh
FROM="your-gmail-address"
AUTH="your-gmail-username"
PASS="your-gmail-password"
FROMNAME="Your Router"
TO="your-email-address"
ntpclient -h pool.ntp.org -s &> /dev/null
sleep 5
echo "Subject: WAN state notification" >/tmp/mail.txt
echo "From: \"$FROMNAME\"<$FROM>" >>/tmp/mail.txt
echo "Date: $(date -R)" >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "I just got connected to the internet." >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "My WAN IP is: $(nvram get wan0_ipaddr)" >>/tmp/mail.txt
echo "Uptime is: $(uptime | cut -d ',' -f1 | sed 's/^.\{12\}//g')" >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
echo "---- " >>/tmp/mail.txt
echo "Your friendly router." >>/tmp/mail.txt
echo "" >>/tmp/mail.txt
cat /tmp/mail.txt | sendmail -H"exec openssl s_client -quiet \
-CAfile /jffs/configs/google_root.pem \
-connect smtp.gmail.com:587 -tls1 -starttls smtp" \
-f"$FROM" \
-au"$AUTH" -ap"$PASS" $TO
rm /tmp/mail.txt
After saving the script disconnect and connect again to internet or reboot router and check your email inbox.
