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Chapter 13Using this method, the SMTP traffic will be forwarded from your host to yourremote shell server securely. However, the connection from the shell server to theultimate destination (SMTP server on mail.example.org in this example) may notbe secure.NTPKeeping time in sync, has more importance than people realize. For example a serverthat sends event logs to another server, using syslog protocol, should be in syncwith each other. Otherwise, the log time will differ from the time,when the eventactually happened. Alternatively a caching web proxy will not remove the expiredcached objects correctly, as it relies on the server's date and time while looking forthe expire field in the http header.The solution for having server times in sync (beside correcting date and timemanually) is the Network Time Protocol (NTP, as per RFC 1305).Before trying to synchronize your clock using NTP protocol, make sureyou have set the correct time zone. To modify the current time zone,use tzsetup(8).SyncingSynchronizing system time to an ntp server can be done manually using thentpdate(8) utility. The ntpdate(8) needs an ntp server name to synchronize with:# ntpdate pool.ntp.orgLooking for host pool.ntp.org and service ntphost found : ferret.eicat.ca9 Nov 00:15:41 ntpdate[72515]: step time server 66.96.30.91 offset138.608584 secThere are plenty of public NTP servers available (see: www.ntp.org).However, it is suggested that you use pool.ntp.org, as it actuallybalances the load between a large pools of NTP servers.You can also have the system run ntpdate automatically during boot up process, byadding the following variable to the rc.conf file:ntpdate_enable="YES"[ 213 ]