Dynamic IP workaround
When running on a NATed computer (e.g. a NAS), this shell script checks an external service for the router's WAN IP in an configurable interval. Whenever it detects a change, an e-mail with the new IP address will be sent via msmtp. As long as the $APIURL is valid, only the $MAILTO definition needs to be adapted.
#!/bin/sh
MAILTO="YOUR_E-MAIL_ADDRESS"
MSG="Subject: Home IP\n\nCurrent IP: "
APIURL="http://api.ipify.org/"
INTERVAL="1800"
GETIP="/usr/bin/curl -s "$APIURL""
SENDCMD="/usr/bin/msmtp"
IP=`$GETIP`
printf "$MSG""$IP" | "$SENDCMD" "$MAILTO"
sleep "$INTERVAL"
while : ; do
IPNEW=`$GETIP`
if [ "$IPNEW" = "$IP" ] ; then
sleep "$INTERVAL"
IPNEW=`$GETIP`
else
IP="$IPNEW"
echo "$MSG""$IP" | "$SENDCMD" "$MAILTO"
fi
done
And here a simple msmtp configuration with TLS enabled – be aware that the mail password is stored on the host computer in plaintext.
### File: ~/.msmtprc or /etc/msmtprc
defaults
auth on
tls on
tls_starttls off
tls_trust_file /etc/ssl/certs/ca-certificates.crt
logfile ~/.msmtp.log
account ACCOUNT_1
host SMTP_SERVER
user USER_NAME
password PASSWORD
from FROM_ADDRESS
account default : ACCOUNT_1