When using a certificate configured for TLS for Apex Central / Apex one as a service in Administration > Settings > Syslog Settings, the following error message appears in the SIEM server or syslog server:
GnuTLS error -110: The TLS connection was non-properly terminated.
This is a known issue in .NET 4.6 and previous versions. However, this error will not impact Apex Central / Apex One as a Service syslog functionality.
The error means that the peer just closed the socket, and did not do a proper TLS shutdown.