dear all

does any one how to activate the log authlog on solaris

Uncomment the following line in /etc/syslog.conf :
or you are talking about the SSH auth.log file ?

thank you ichanged it but do you know how to start the service because
the log still empty

or there is another way is missing after changed the file /etc/syslog.conf

Just editing the file isn't enough. Run 'pkill -HUP syslogd' so that syslogd will re-read the config file.