Note: you've seen many commandline instructions but they all suffer
from the fact that they reset certain, definitely not wanted, defaults.
That's why the setup is done in the registry and not the commandline.

You've got the w32time/ntpd up and running as a client, so the most
basic item of connecting out to a time server is taken care of.

Now we have to tell XP to act as a time _server_ for requesting clients
(your Linux box) as well.

The first thing is to shut down w32time while we edit the registry.
At commandline enter:
net stop w32time
We will re-start it when we are done.

ONE: Enable NTPServer

I suspect this is the "new way" for XP SP2, so we will check to see if
the registry subkey already exits.  See a.  If it does not exist we
will use the "old way" next below.
This is documented for W2K3:  << we'll revisit this doc below
To do this, follow these steps:
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\ NtpServer\Enabled
If this subkey does exist, skip the "old way" and go to "Doc for W2K3
found here:".  If this subkey does not exist we use the "old way".

This is the "old" way and I'm not sure if this is now needed, but it
won't hurt.
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters
If LocalNTP already exists (in right pane) skip b?.and c?.
b?. From the Edit menu, select New, DWORD Value.
this may not be needed, LocalNTP exists already?
c?. Enter the name LocalNTP, then press Enter.
this may already exist, don't add a new one if so
d. Right-click LocalNTP, select Modify, set it to 1.  Click OK.

This begins the series of changes that we must make.  Other approaches
(especially pre-SP2) may work as well, but I've confirmed/coroborated
the following steps:

Doc for W2K3 found here:
http://www.isaserver.org/pages/article_p.asp?id=1291
(From MS docs but formatted better for my purposes.  The gui guidance
may also be useful to you)

Have handy:
How to configure an authoritative time server in Windows XP
http://support.microsoft.com/default.aspx?scid=kb;en-us;314054
(you already have this, IIRC)

To configure the Windows Time service to use an external time source,
follow these steps:
(Done this already?  Double check.  You're in the neighborhood anyway,
so double check!:)
1. Change the server type to NTP. To do this, follow these steps:
a. Click Start, click Run, type regedit, and then click OK.
b. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters\Typ e
c. In the right pane, right-click Type, and then click Modify.
d. In Edit Value, type NTP in the Value data box, and then click OK.

2. Set AnnounceFlags to 5. To do this, follow these steps:
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config\Announc eFlags
b. In the right pane, right-click AnnounceFlags, and then click Modify.

c. In Edit DWORD Value, type 5 in the Value data box, and then click
OK.
me -- This must be set correctly or w32time may be flakey.  This tells
XP to treat _your_ w32time as a reliable source to anyone who asks
(ie., Linux).  5 comes from this
1(Always a time server) + 4(Always a reliable time server) = 5

3. Enable NTPServer. To do this, follow these steps:
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\ NtpServer\Enabled
b. In the right pane, right-click Enabled, and then click Modify.
c. In Edit DWORD Value, type 1 in the Value data box, and then click
OK.
me -- Here it is!  We told XP that you want to act as a ntp time
server.

4. Specify the time sources. To do this, follow these steps:
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Parameters\Ntp Server
b. In the right pane, right-click NtpServer, and then click Modify.
c. In Edit Value, type *Peers* in the Value data box, and then click
OK.
Note *Peers* is a placeholder for a space-delimited (ie., space
separated - me) list of peers from which your computer obtains time
stamps. ****Each DNS name that is listed must be unique. You must
append ,0x1 to the end of each DNS name. If you do not append ,0x1 to
the end of each DNS name, the changes made in step 5 will not take
effect.****  emphasis added - me  You can use IP addres(ses) here.

me -- Some swear by DNS names, others not.  Depends on how reliable
your DNS server is and the likelihood that the time server's IP will
change (names tend to remain the same).  You may be tempted to use one
of the pool.ntp.org NTP 'pool.' members, but I do not recommend it for
your use.  It's a round robin distribution of servers and you can't be
sure how close they are -- you need servers you _know_ are located
close to you.  Later you can add/manage this list from gui?  Need to
find where.

me again -- found some gui guidance.  See at end of post.

Here is yet another list of public time servers -- several in Bay area.
http://support.microsoft.com/default.aspx?scid=kb;en-us;262680

me -- The following is the one you've had "trouble" with.  See my
previous post on this matter if you haven't already.
http://groups-beta.google.com/group/microsoft.public.windowsxp.genera...
5. Select the poll interval. To do this, follow these steps:
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\TimeProviders\ NtpClient\SpecialPollInterval
b. In the right pane, right-click SpecialPollInterval, and then click
Modify.
c. In Edit DWORD Value, type *TimeInSeconds* in the Value data box, and
then click OK.
Note *TimeInSeconds* is a placeholder for the number of seconds that
you want between each poll. A recommended value is 384. This value
configures the Time Server to poll every 15 minutes.
me -- You gotta get this out of the default setting which is once a
week for a stand-alone machine!
me again -- Notice the 384 suggested here; it implies that they are
looking for a hex value -- hex should be checked in the Vaule data box.
While a decimal value would probably work, the fact that they are
suggesting a hex value implies that the code is somehow more efficient
if restricted to some hex values (which 384 is!).  Just enter 384  --
it is hex for 900 seconds=15 minutes.  With your likely line
quality/speed it probably makes no sense for a lower value and too high
may obscure network conditions like spikes.

6. Configure the time correction settings. To do this, follow these
steps:
a. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\W32Time\Config\MaxPosP haseCorrection
b. In the right pane, right-click MaxPosPhaseCorrection, and then click
Modify.
c. In Edit DWORD Value, select Decimal in the Base box.
d. In Edit DWORD Value, type *TimeInSeconds* in the Value data box, and
then click OK.
Note *TimeInSeconds* is a placeholder for a reasonable value, such as 1
hour (3600) or 30 minutes (1800). The value that you select will depend
upon the poll interval, network condition, and external time source.
The default value for stand-alone clients and servers is 54,000 (15 hrs
-- YUK!).
me -- 3600 should be a good start.  You may decide that the special
value -1 is needed -- says to always correct (but I'm not sure about
the implications of this in your situation.  It is the default if
connected to a lan Domain).

These are the "basics" and there are many more to explore.  I'll
include the most interesting ones in another post to keep the sections
smaller.

To get an idea whether it's synching set your XP clock _back_ about 5
minutes.  With luck it may synch immediately or take as much as 15
minutes (the next poll) to ask for the time.  Reboot should also be
immediate, but may not be inconvenient.  You decide.

Re-start your time service from this commandline:
net start w32time

How to Configure Services
How to Start, Stop, Pause, Resume, or Restart a Service
NOTE: You must be logged on as an administrator or a member of the
Administrators group to complete this procedure. If your computer is
connected to a network, network policy settings may also prevent you
from completing this procedure.
1.
Click Start, click Control Panel, click Performance and Maintenance,
click Administrative Tools, and then double-click Services.
2.
In the Details pane, click the service.
3.
On the Action menu, click Start, Stop, Pause, Resume, or Restart.
4.
To configure the startup parameters for a service, right-click the
service, click Properties, and then type the parameters in the Start
parameters box before you click Start. These settings are used only
once and are not saved. A backslash character (\) is treated as an
escape character; type two backslashes for each backslash in a
parameter.
Notes:
·
If you stop, start, or restart a service, any dependent services are
also affected.
·
Changing the default service settings might prevent key services from
running correctly. Use caution when you change the Startup Type and Log
On As settings for services that are configured to start automatically.

Next installments will cover w32time tweaks and maintainence and
address some firewall issues that _may_ arise (hopefully not).

till next time,
prg
email above disabled

Note that computers running Windows XP use the Network Time Protocol
(NTP), while computers running Windows 2000 use the Simple Network Time
Protocol (SNTP).