edit syslog-ng.config

nano /etc/syslog-ng/syslog-ng.conf

add end file

source s_fortigate {
udp(ip(0.0.0.0) port(514));
tcp(ip(0.0.0.0) port(514));
};
destination d_fortigate {
file(
“/var/log/fortigate/$HOST-$YEAR$MONTH$DAY.log”
perm(644)
create_dirs(yes)
);
};
log { source(s_fortigate); destination(d_fortigate); };

# or —————————————
source s_net { udp(ip(0.0.0.0) port(514)); };
#destination d_router { file(“/var/log/syslog”); };
destination d_router { file(“/var/log/router/$HOST-$YEAR$MONTH$DAY.log”); };

log { source(s_net); destination(d_router); };

New chmod 644
chmod 644 /var/log/syslog