Mail relaying

Export StartTLS certificate from SMTP server

René Jorissen on May 5, 2015 2 Comments • Tags: #certificate #export #smtp #smtpoffice365com #starttls

While configuring Office365 as the messaging (SMTP) server within Aruba ClearPass, I needed to upload the certificate from the StartTLS session to the certificate trust list from ClearPass. I had to export the certificate for smtp.office365.com via the following OpenSSL command: openssl s_client -showcerts -starttls smtp -crlf -connect smtp.office365.com:587 After running the command, you will see … Read More

Other stuff...

OpenSSL for testing TLS

René Jorissen on February 17, 2011 1 Comment • Tags: #crlf #openssl #smtp #starttls #s_client #s_server #test #tls

I was looking for a way to test the TLS configuration of a secure mail server and stumbled across a website called “OpenSSL Command-Line HOWTO”. This websites explains how to test a TLS connection using OpenSSL. The s_client and s_server options provide a way to launch SSL-enabled command-line clients and servers. There are other examples … Read More