Letsencrypt update script, restart service if success and notify with ssmtp

update.sh

SERVER="Ubuntu (192.168.1.54)"
EMAIL='hello@gmail.com'
ALERTMESSAGE='/tmp/ALERTMESSAGE_cert.tmp'
 
if /usr/bin/openssl x509 -checkend 86400 -noout -in /etc/letsencrypt/live/my.domain.eu/fullchain.pem
then
  echo "Certificate is good for another day!"
else
 
echo "To: $EMAIL" > $ALERTMESSAGE
echo "From: $FROM" >> $ALERTMESSAGE
echo "Subject: LetsEncrypt SSL Renew on $SERVER" >> $ALERTMESSAGE
echo "" >> $ALERTMESSAGE
echo "Certificate has expired or will do so within 24 hours!" >> $ALERTMESSAGE
echo "Start LetsEncrypt" >> $ALERTMESSAGE
/home/username/scripts/letsencrypt/letsencrypt-auto renew --renew-hook "systemctl restart unifi.service" >> $ALERTMESSAGE
 
/usr/sbin/ssmtp $EMAIL < $ALERTMESSAGE
 
fi