I made the change as suggested and it is complaining:

source s_net {
network(ip('<our IP>') port(<our port>)
transport("tls")
tls( key-file("/usr/local/etc/hostcert.key")
cert-file("/usr/local/etc/hostcert.pem")
peer_verify(optional-untrusted)

ssl-options(no-sslv2, no-sslv3, no-tlsv1)

)
);
};

I got the following error when I tried to start it:

-bash-4.1$ sudo service sys-ng1 start

syslog-ng service starting.

Error parsing afsocket, syntax error, unexpected LL_IDENTIFIER, expecting ')' in /opt/splunk/usr/local/etc/syslog-ng.conf at line 49, column 9:

        ssl-options(no-sslv2, no-sslv3, no-tlsv1)

        ^^^^^^^^^^^

syslog-ng documentation: http://www.balabit.com/support/documentation/?product=syslog-ng

mailing list: https://lists.balabit.hu/mailman/listinfo/syslog-ng

From: <syslog-ng-bounces@lists.balabit.hu> on behalf of "thejaguar@tutanota.de" <thejaguar@tutanota.de>
Reply-To: Syslog-ng users' and developers' mailing list <syslog-ng@lists.balabit.hu>
Date: Tuesday, August 16, 2016 at 5:53 PM
To: Joe Lupo <Joseph.Lupo@T-Mobile.com>
Cc: Syslog-ng users' and developers' mailing list <syslog-ng@lists.balabit.hu>
Subject: Re: [syslog-ng] Disabling SSLv3 with Syslog-NG

its part of tls options so 

tls( key-file("/usr/local/etc/hostcert.key")

cert-file("/usr/local/etc/hostcert.pem")
peer_verify(optional-untrusted)

ssl-options(no-sslv3,no-tlsv1) 

)
);
The Jaguar

16. Aug 2016 12:13 by Joseph.Lupo@T-Mobile.com:

The syslog-ng documentation is very unclear. Where would we put the ssl-options(no-sslv2, no-sslv3, no-tlsv1) entry for disabling sslv2, sslv3 and tlsv1?

The following works for enabling TLS on our host, but I can’t figure out where to insert the ssl-options.

source s_net {
network(ip('<our IP>') port(<our port>)
transport("tls")
tls( key-file("/usr/local/etc/hostcert.key")
cert-file("/usr/local/etc/hostcert.pem")
peer_verify(optional-untrusted))
);
};



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