SSL
# check certificate
https://www.ssllabs.com/ssltest/analyze.html
http://www.panticz.de/Check-SSL-TLS-server-encryption-support
# determine SSL certificate expiration date
openssl x509 -enddate -noout -in www.example.com.pem
# list certificate domains
cat cert.pem | openssl x509 -text | grep DNS
openssl s_client -showcerts -connect www.example.com:443 | openssl x509 -text | grep DNS
# Letsencrypt
http://www.panticz.de/letsencrypt
# remove password from private key
openssl rsa -in www.example.key.pass -out www.example.key
# cat / deploy certificate to remote host