[ntp:questions] Windows Time with NTPv4

Evandro Menezes evandro at mailinator.com
Thu Mar 13 16:03:19 UTC 2008

On Mar 13, 3:56 am, Martin Burnicki <martin.burni... at meinberg.de>
> Do the Windows system run ntpd or w32time? If they run ntpd then
> authentication could be configured correctly. I don't know how any version
> of w32time could be configured to support NTP's symmetric keys or even
> autokey.

They run w32time.

> This seems to indicate that ntpd is running on the XP machines and has been
> configured correctly with authentication.

Actually not.  I had this in ntp.conf:

restrict default kod limited nopeer
tos orphan 4
enable bclient
disable auth

Then, the w32time systems appeared as servers in the output of "ntpq -
p" and "ntpdc -c listpeers" confirmed their status as peers.

When I removed the last line above, as w32time doesn't support
authentication keys, the w32time systems stopped showing up as
servers, even though their association mode remained 1.  So w32time
was happy, believing it was a peer (if it indeed behaves as a peer is
left to be demonstrated), and NTP kept on working without the
interference of w32time in its choice of servers.

> Of course the admin of a NTP server does not want his NTP server's time be
> changed just because some dumb client sends some packet asking to do so.

But I think that with the proper restrictions NTP will do the right

> This is what happens with w32time which under certain conditions sends
> "peer" requests instead of "client" requests. Since those w32time clients
> have neither been configured nor authenticated as peers, the question is
> how they should be handled by ntpd.

I think that they're being handled just fine by NTP.  NTP does what
ntp.conf tells it to do and it can handle w32time stupidity just fine
as in my case above.


More information about the questions mailing list