script to auto update letsencrypt certs for debian lighttpd installation (based on script by Danny Tuppeny)

letsencrypt-update-lighttpd

#!/usr/bin/env bash
#
# Update letsencrypt on a lighttp installation
#
# if you installed letsencrypt in a non-standard location you
# can set the LEDIR env var before you run this script
#

# setup letsencrypt install directory
STDLEDIR=/opt/letsencrypt
LEDIR=${LEDIR:-$STDLEDIR}

echo "##### Starting renewal $(date) at $LEDIR #####"

# check path to letsencrypt-auto tool
if [ ! -f "$LEDIR/letsencrypt-auto" ]; then
  echo "Error: letsencrypt-auto script not found, is letsencrypt installed at $LEDIR?"
  exit 1
fi

# renew all certs in live directory
$LEDIR/letsencrypt-auto renew

# rebuild the cert combined.pem
for domain in /etc/letsencrypt/live/* ; do
  pushd $domain
  echo "Rebuilding cert for: $(basename $domain)"
  cat privkey.pem cert.pem > combined.pem
  popd
done

# reload lighttpd
/etc/init.d/lighttpd force-reload

echo "##### Finished renewal $(date) at $LEDIR #####"

exit 0

# recommended cron installation (run crontab -e as root)
30 2 * * 1 <abs-path>/letsencrypt-update-lighttpd >> /var/log/le-renew.log

Created a fork: https://gist.github.com/qwertychouskie/065007bdfcf58b6c4e8354ac60cd587e
Useful if you use the packaged version from jessie-backports.