The Windows Time Service

Q. Should I disable the "Windows Time" service on my Windows 2000 or Windows XP system?

A. It depends. Read up on the Windows Time Service.

Very interesting. I still prefer NetTime, but this whitepaper has got me wondering if W32Time can't cooperate with NetTime in a constructive way.

Advantages of using NetTime over W32Time are legion. You can configure all NetTime options in one easy-to-use window. W32Time requires learning command-line flags, or setting certain values with regedit if you want to retain them between restarts.

NetTime easily lets you pick your own NTP servers, configure how often you sync, and whether or not you wish to run a turnkey NTP server on your own system. W32Time lets you do all of this, too, but guess what? You have to read the white paper to learn how.

NetTime may not be your cup of tea, though. It's written in Pascal and will, by default, resync every ten minutes. If your NTP server is dodgy, or you're borrowing some generous institution's Stratum-2 server, you may wish to be polite and back the frequency of requests down to every few hours or so. Even modern PCs have such shoddy system clocks that they will drift by a few seconds a day if you let them, so syncing less than once a day is just plain sloppy. W32Time by comparison has a complicated, but kinder, retry schedule: sync at startup, then every 45 minutes thereafter until the system has successfully synced three consecutive times, then back the frequency down to every eight hours.

So basically, if you just plain don't give a damn about what time your system clock says, go ahead to turn off the Windows Time service. Otherwise, keeping it is a matter of deciding if it meets your time synchronization needs. I know it doesn't meet mine.

Here's why: what servers, by default, will W32Time use? The answer: whichever ones you tell it to use by configuring your Active Directory Primary Domain Controller. Failing that, who knows? My firewall doesn't talk to a PDC. In fact, there is no PDC. And so just leaving Windows Time on and letting it work its mojo won't fly on my home network: the firewall will actively interfere with W32Time's attempts to sync to anything that isn't local. NetTime, on the other hand, let's me put, say, "129.22.4.3" as the host, and I can then turn around and put that exact same value into /etc/pf.conf and, wouldn't you know it, the damn thing just works.