Need to set up the SBS box as an authoritative Time Server?

re: Need to set up the SBS box as an authoritative Time Server?

BP — Thu, 04 Jan 2007 18:07:16 GMT

I dont need to open a port to get web pages or pop mail from an external source, why would I need to open a port to get the time?

re: Need to set up the SBS box as an authoritative Time Server?

mark — Thu, 04 Jan 2007 12:58:06 GMT

Re: BP's post

The SBS box is a client of the external time server, but is also the authoritative time server in your windows domain, as is any forest root server in an AD by default. You only need to open the port if, as Susan suggests, you wish to allow the SBS box to get its time info from an external source.

On my network, my firewall has NTP server capability, so I just point my SBS box to get its time sync from there. The firewall syncs with pool.ntp.org. Therefore I don't have to allow the port 123 traffic

re: Need to set up the SBS box as an authoritative Time Server?

Tim Long — Thu, 04 Jan 2007 06:04:22 GMT

That's all useful information. The Windows time service is great for general business use but as an astronomer I need a more accurate time reference for some of my applications. On my home/office SBS network I use a program called Tardis2000 on the server and a related program called K9 (which is a minimal client application) that runs on the workstations. Both applications run as services so they are fault tolerant and self-starting. Tardis2000 uses normal SNTP to set the time from the internet pool time servers. It adapts the interval with which it adjusts the time based on the size of adjustment made and it also attempts to trim the system clock speed so that fewer updates are necessary. Having set the server time accurately, Tardis2000 then re-broadcasts the time using broadcast-NTP on the internal network, about once a minute. The K9 client on the workstations listens for these NTP broadcasts and adjust their time accordingly. This keeps my entire network synchronised to itself and UTC with an accuracy of better than 100 milliseconds, which is fine for what I need.

re: Need to set up the SBS box as an authoritative Time Server?

BP — Thu, 04 Jan 2007 04:37:05 GMT

First, if the Windows 2003 SBS is acting as a client, I dont belive there is a need to open port 123 in any firewall. Certainly if you are providing sntp services outside the firewall, but otherwise no. Any comments?

Second, can anyone state with authority how a default SBS 2003 install is configured or if it is configured at all to sync time with any outside source? Is any of this necessary on a default install?

re: Need to set up the SBS box as an authoritative Time Server?

Matt — Thu, 04 Jan 2007 03:33:04 GMT

You can condense that all down into a single command by adding /update at the end:

w32tm /config /manualpeerlist:ntp_servername /syncfromflags:MANUAL /update

No need to restart the service in XP or 2003 (or Vista). Update will also force a sync.

re: Need to set up the SBS box as an authoritative Time Server?

Nick — Thu, 04 Jan 2007 03:12:11 GMT

Kind of random... but I did a short write-up on the basics behind Windows time synchronization a while back... thought it might prove useful to link here...

http://addicted-to-it.blogspot.com/2006/01/kb-introduction-to-windows-time.html