[ntp:questions] Windows Time with NTPv4

Ryan Malayter malayter at gmail.com
Mon Mar 10 14:55:13 UTC 2008

Okay, I just did some packet captures. It appears that Vista, when
configured *only* with a time server host name or IP address, will
first issue an NTP client mode request, and then an NTP symmetric
active requirest a few miliseconds later.

I imagine this default behavior is there to make w32time work in the
same "broken" fashion that was used in Windows 2000. Backwards
compatability is a bitch. Do Windows 2000 domain controllers ignore
client-mode packets or someting? I don't have one to test with.

When a Vista machine is explicitly configured to use a client mode
association, like so:
   w32tm /config /manualpeerlist:pool.ntp.org,0x8
it issues only client-mode queries, as you would expect.

I will do some further captures with XP clients, but I expect the
results to be the same.

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