Added guide on openssl

openssl.md

@@ -0,0 +1,20 @@
+# OpenSSL
+
+```bash
+# Verify a PEM  
+openssl x509 -inform PEM -in  agent.crt.pem  -noout -text
+
+# Convert cert to PEM format
+openssl x509 -in rabbitmq.crt -outform PEM -out rabbitmq.crt.pem
+
+# Connect to server and show certs
+openssl s_client -showcerts -connect pluralsight.com:443
+
+# To debug openssl/certs on a server start openssl server ... 
+openssl s_server -key key.pem -cert cert.pem
+
+# .. connect to server
+openssl s_client -connect server.com:443 -ssl3
+```
+
+- https://blog.jorisvisscher.com/2015/07/22/create-a-simple-https-server-with-openssl-s_server/