[gX:~] # cat syslog.conf
...
local7.info                                   /var/log/dhcpd.log
...

[gX:~] # touch /var/log/dhcpd.log

[gX:~] # /etc/rc.d/syslogd reload

[gX:~] # logger -t dhcpd -p local7.info "Starting dhcpd..."

[gX:~] # cat /etc/newsyslog.conf
...
/var/log/dhcpd.log                       600  7     10   *     J

[gX:~] # cat logger.sh
while :
do
  logger -t dhcpd -p local7.info "Message 1"
  logger -t dhcpd -p local7.info "Message 2"
done

[gX:~] # sh logger.sh
...
<Ctrl>-C

[gX:~] # tail -f /var/log/dhcpd.log
...
<Ctrl>-C

[gX:~] # newsyslog

[gX:~] # ls -l /var/log/dhcpd*

[gX:~] # cat /etc/rc.conf 
...
syslogd_flags="-a 192.168.X.0/24"

Сокращенная форма 192.168.X/24 не распознается!

[gX:~] # /etc/rc.d/syslogd restart

[g50:~] # cat /etc/syslog.conf
*.*                                           @gX
...

[g50:~] # /etc/rc.d/syslogd restart

[gX:~] # cat syslog.sh 
#!/bin/sh
while read m
do
        if expr "$m" : '.*login.*' > /dev/null
        then
                echo $m | mail -s login root
        fi
done

[gX:~] # chmod +x syslog.sh

[gX:~] # cat /etc/syslog.conf
...
auth.*                                        | /root/syslog.sh 
...