The default logging for samba on CentOS is to log to
/var/log/samba/log.smbd and out of the box the
log file setting is
/var/log/samba/%m (the connecting machine log) so it looks like someone has made changes to at least some of the defaults.
syslog directive says this
This parameter maps how Samba debug messages are logged onto the system syslog logging levels. Samba debug level zero maps onto syslog LOG_ERR, debug level one maps onto LOG_WARNING, debug level two maps onto LOG_NOTICE, debug level three maps onto LOG_INFO.
All higher levels are mapped to LOG_DEBUG.
This parameter sets the threshold for sending messages to syslog. Only messages
with debug level less than this value will be sent to syslog. There still will be
some logging to log.[sn]mbd even if syslog only is enabled.
Default: syslog = 1
This means that under default conditions LOG_ERR messages will be logged to syslog too. You gould put
syslog = 0
/etc/smb.conf which should stop anything going to syslog.
You'll need to check you .etc/samba/smb.conf file for
It would probably be a good idea to check through the smb.conf documentation too for other logging options.