FTPs (TLS/SSL) AUTH not understood

[nrg]

I just migrated from a CentOS 5 server with Plesk 11.5 to a new server with CentOS 6.6 Plesk 12.

All customers, resellers, domains, subscriptions and even FTP users have been migrated fine (great tool btw).

There's only one thing what I cannot get to work on the new server: FTPs (TLS/SSL), this always results in "AUTH not understood".

The security and FTP settings are exactly the same as the old server (where FTPs worked fine), so I guess something is missing on the server.

What can I do to have a proper working FTPs with TLS/SSL?

 

[abdi]

This should be clues on where to look:
https://forums.proftpd.org/smf/index.php?topic=11156.0

 

[nrg]

I compared both /etc/proftpd.conf on old and new server, and found out the <IfModule mod_tls.c> part was missing in <Global>:

<Global>
DefaultRoot    ~        psacln
AllowOverwrite        on
<IfModule mod_tls.c>
    # common settings for all virtual hosts
    TLSEngine on
    TLSRequired off

    TLSLog /usr/local/psa/var/log/ftp_tls.log

    TLSRSACertificateFile /usr/local/psa/admin/conf/httpsd.pem
    TLSRSACertificateKeyFile /usr/local/psa/admin/conf/httpsd.pem

    # Authenticate clients that want to use FTP over TLS?
    TLSVerifyClient off

    # Allow SSL/TLS renegotiations when the client requests them, but
    # do not force the renegotations.  Some clients do not support
    # SSL/TLS renegotiations; when mod_tls forces a renegotiation, these
    # clients will close the data connection, or there will be a timeout
    # on an idle data connection.
    TLSRenegotiate none

    # As of ProFTPD 1.3.3rc1, mod_tls only accepts SSL/TLS data connections
    # that reuse the SSL session of the control connection, as a security measure.
    # Unfortunately, there are some clients (e.g. curl) which do not reuse SSL sessions.
    TLSOptions NoSessionReuseRequired
</IfModule>
</Global>

After adding this, everything works as intended.