Problem with Let's Encrypt Certificate

Robert L Mathews
Fri, 17 Feb 2017 18:28:28 -0000

On 2/17/17 8:58 AM, Bastian Sebode wrote:

> I uploaded two Wireshark tracefiles, further logs and dovecot -n

Looking at your dovecot -n, you're using two different files here:

ssl_cert = </etc/ssl/sebode-online.de/chain.pem
ssl_key = </etc/ssl/sebode-online.de/key.pem

Are you sure these two files match, and contain the right things in the
right order?

We use a single PEM file as input for both of these parameters, and that
PEM file contains, in this order:

-----BEGIN RSA PRIVATE KEY-----
...
-----BEGIN CERTIFICATE-----
...
-----BEGIN CERTIFICATE-----

... where the first BEGIN CERTIFICATE is the specific hostname one, and
the second BEGIN CERTIFICATE is the Let's Encrypt X3 intermediate
certificate that ends with "DNFu0Qg==".

You're also manually specifying these non-default parameters:

ssl_cipher_list = ...
ssl_prefer_server_ciphers = yes
ssl_protocols = !SSLv2 !SSLv3

For testing, I would simplify. Does it work without any of those three
things set?

--
Robert L Mathews, Tiger Technologies, http://www.tigertech.net/