As already announced in the last weeks, we started investigating the CentOS infra services/nodes on which we could add TLS support (if not already supporting it). After the work done at the http/https level, we decided to add TLS
support for the mail servers within the CentOS.org infrastructure.

We’ve so implemented today the STARTTLS feature on our MX nodes, both for incoming and outgoing mails. Please note that we’ve configured Postfix for “Opportunistic TLS”, meaning that it should be transparent for you :
* If your SMTP server is also configured for TLS support, traffic between your SMTP server (or the one from your ISP, that you’re using as SMTP relay) and our servers will be encrypted.
* If not, it will still be sent in clear, as before

More information about “Opportunistic TLS” support for Postfix here :
http://www.postfix.org/TLS_README.html#client_tls_may

Should you encounter an issue, feel free to either report it on https://bugs.CentOS.org, or in #CentOS-devel on irc.freenode.net.

on behalf of the Infra team,
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