[syslog-ng] CentOS7 syslog-ng 3.5.6: TLS: SSL routines:SSL3_READ_BYTES:tlsv1 alert unknown ca

[Schulte, Klaus (Nokia - DE/Ulm)]

Dear all,

I've this source settings for TLS:

source s_tcp_tls {
   network(  transport("tls")
             ip(10.46.130.65) port(6514)
             tls(
                   peer-verify("optional-untrusted")
                   key-file("/etc/syslog-ng/key.d/syslog-ng.key")
                   cert-file("/etc/syslog-ng/cert.d/syslog-ng.cert")
             )
   );
};

But when a client connects via TCP/TLS to the syslog-ng service..

In syslog-ng these messages are showing up:

syslog-ng starting up; version='3.5.6'
Syslog connection accepted; fd='12', client='AF_INET(10.46.160.78:48075)', local='AF_INET(10.46.130.65:6514)'
SSL error while reading stream; tls_error='SSL routines:SSL3_READ_BYTES:tlsv1 alert unknown ca'
I/O error occurred while reading; fd='12', error='Connection reset by peer (104)'
Syslog connection closed; fd='12', client='AF_INET(10.46.160.78:48075)', local='AF_INET(10.46.130.65:6514)'
Closing log transport fd; fd='12'

I don't know why syslog-ng is proving the CA?
As far as I know the configuration is a non-mutual authentication - so the CA shouldn't play a role in this - is this correct?

The client sends messages in RFC5424 format.

Any help is appriciated - I've no clue what's going wrong.

Best regards
  Klaus
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