[ntp:questions] Windows time question.
nomail at example.com
Fri Apr 22 16:37:12 UTC 2011
unruh <unruh at wormhole.physics.ubc.ca> wrote:
> On 2011-04-22, Rob <nomail at example.com> wrote:
>> Hal Murray <hal-usenet at ip-64-139-1-69.sjc.megapath.net> wrote:
>>>>I would have hoped that the pool folk kept their documentation up-to-date,
>>>>so I'll post that on their list. You didn't mention how to control the
>>>>number of servers uses - is it just multiple "pool" entries?
>>> You only need one pool command.
>>> pool <server-name>
>>> will use as many addresses from server-name as it needs.
>>> If it doesn't get enough with the first DNS lookup, it will try
>>> again in a minute or so, and keep trying until it gets enough.
>>> The default is to collect 10 servers.
>> If I were involved in the pool I would call that abuse!
>> The pool DNS lookup now returns 3 servers, used to be 5.
>> When everyone uses 10 servers the load on the pool as a whole is
>> twice what it would need to be, and 3 times what would be the minimum
>> reasonable value.
> I agree. It is absurd. It seems to indicate that the ntp folk really
> really do not trust the pool, and figure that if you get fewer than 10, you have a
> reasonable chance that a majority will deliver bad time. Ie, they appear
> to feel that the pool is a pretty useless souce of time.
And that is a bit strange, because if anything the pool is more reliable
than a random NTP server!
Pool servers may not be accurate to the microsecond, but they are
centrally monitored to see if they return reasonably accurate time,
and when they don't they are taken out of the set that the DNS returns.
So a free running server that is returning a time in the wrong year is
certainly not going to be a member of the pool.
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