I was using ntpdate (the smallest ntp client) with crontab for awhile too. This was mostly on an older NAS a few years ago. Now, I stick with running the daemon configured as a client only (for servers and workstations). As you correctly stated, it's a fairly small footprint, and the gain in precision makes it worth in most cases I can think of. Also have been running constantly on my rasp pis now for a few years (you almost have to with the lack of time retention on them). So, IMO, not much performance / memory gleaned using the minimal client like the old days (even then it was pretty minimal). You lose a little ground on security if not configured properly (ie. as a server on a lax network intended to be configured as a client only). -- Jeremy MountainJohnson Jeremy.MountainJohnson at gmail.com On Wed, Sep 9, 2015 at 12:10 PM, Mike Miller <mbmiller+l at gmail.com> wrote: > For years I have been using something like this in a root crontab to adjust > the time every 6 hours: > > 10 4,10,16,22 * * * /usr/sbin/ntpdate-debian > > On this machine it was going off by about 0.17 seconds every 6 hours and it > was pretty consistent: > > 7 Sep 16:10:10 ntpdate[11932]: adjust time server 91.189.89.199 offset > 0.172249 sec > 7 Sep 22:10:09 ntpdate[13949]: adjust time server 91.189.89.199 offset > 0.173074 sec > 8 Sep 04:10:10 ntpdate[15490]: adjust time server 91.189.89.199 offset > 0.174787 sec > 8 Sep 10:10:09 ntpdate[18482]: adjust time server 91.189.89.199 offset > 0.169422 sec > > Then I noticed that on a newer Ubuntu installation I didn't have the > crontab, but the timing was even better. I'm pretty sure that newer Ubuntu > installs let the user to choose to set date/time "automatically," and that > was what I had chosen. > > So I had to wonder what it *really* was doing. I think it was running ntpd. > > USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND > ntp 23926 0.0 0.0 39832 2264 ? Ss Sep08 0:01 > /usr/sbin/ntpd -p /var/run/ntpd.pid -g -c /var/lib/ntp/ntp.conf.dhcp -u > 119:128 > > So I installed the ntp package like so: > > sudo apt-get install ntp > > That automatically set everything up and started it running. It can be > called with the service command to ntp... > > sudo service ntp [start stop restart] > > ...which runs the script here: > > /etc/init.d/ntp > > That seems to keep the clock set very precisely. > > I guess the downside is that it is always running, but it if is using no > more than 2.3 MB, that isn't a problem. > > Is this what everyone is doing these days? > > Mike > _______________________________________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/mailman/listinfo/tclug-list