syslog_ng cannot start succesfully

In our system, we try to start syslog_ng, but found it cannot start up succesfully.

log here:

sh-4.3# /usr/sbin/syslog-ng -Fedv 2>&1 | tee -a syslog-dbg.log

WARNING: Configuration file format is too old, syslog-ng is running in compatibility mode Please update it to use the syslog-ng 3.5 format at your time of convinience, compatibility mode can operate less efficiently in some cases. To upgrade the configuration, please review the warnings about incompatible changes printed by syslog-ng, and once completed change the @version header at the top of the configuration file.;

Starting to read include file; filename='/etc/syslog-ng/scl.conf', depth='1'
Global value changed; define='scl-root', value='/usr/share/include/scl'
Global value changed; define='include-path', value='/etc/syslog-ng:/usr/share/include'
Starting to read include file; filename='/usr/share/include/scl/system/plugin.conf', depth='2'
Module loaded and initialized successfully; module='system-source'
Finishing include; filename='/usr/share/include/scl/system/plugin.conf', depth='2'
Starting to read include file; filename='/usr/share/include/scl/pacct/plugin.conf', depth='2'
Reading path for candidate modules; path='/usr/lib/syslog-ng'
Reading shared object for a candidate module; path='/usr/lib/syslog-ng', fname='affile.so', module='affile'
Registering candidate plugin; module='affile', context='source', name='file', preference='0'
Registering candidate plugin; module='affile', context='source', name='pipe', preference='0'
Registering candidate plugin; module='affile', context='destination', name='file', preference='0'
Registering candidate plugin; module='affile', context='destination', name='pipe', preference='0'
Reading shared object for a candidate module; path='/usr/lib/syslog-ng', fname='afprog.so', module='afprog'
Registering candidate plugin; module='afprog', context='source', name='program', preference='0'
Registering candidate plugin; module='afprog', context='destination', name='program', preference='0'
Reading shared object for a candidate module; path='/usr/lib/syslog-ng', fname='afsocket-notls.so', module='afsocket-notls'
Registering candidate plugin; module='afsocket-notls', context='source', name='unix-stream', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='unix-stream', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='unix-dgram', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='unix-dgram', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='tcp', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='tcp', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='tcp6', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='tcp6', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='udp', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='udp', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='udp6', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='udp6', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='syslog', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='syslog', preference='0'
Registering candidate plugin; module='afsocket-notls', context='source', name='network', preference='0'
Registering candidate plugin; module='afsocket-notls', context='destination', name='network', preference='0'
Reading shared object for a candidate module; path='/usr/lib/syslog-ng', fname='afsocket-tls.so', module='afsocket-tls'

The syslog_ng cannot finish now, stop here.
Could anyone help with this?