time synchronization

[Elena Leontieva]

I wonder how you synchronize computers in your environment.

Are you using public time server on the Internet (ISP or somethig else) and go along with security risks?

If anybody has a dedicated time server (GPS based) behind a firewall what is a cost associated with it.

Will appreciate your comments.
Elena.

[Mark Greene_1 · Accepted solution]

All of our systems are pointed to a wintel box that is a dedicated time server. That box is pointed to the navy time servers (tic and toc). The important part for us is that we have integrity with time among our servers, not that we are accurate to the millisecond with the rest of the world. Your needs will vary, depending on how much real-time interaction you have going on with systems off of your LAN.

mark

[Pete Randall]

Elena,

I use publicly available NTP server(s).


Pete

[Robert-Jan Goossens]

Hi Elena,

we use a gps based timeserver on our internal network. I'm not allowed to open any ports on the firewall.

http://www.endruntechnologies.com/ntp-server.htm

Kind regards,
Robert-Jan

[Elmar P. Kolkman]

There are lots of ways. We have GPS receivers and use them to sync with, but there is no reason not to use the internet to sync with. As for costs: those GPS receivers are more then 7 years old, so I've no idea about the current price of them.
If you select several servers on the internet all those servers would have to be compimised before you run into problems. And then the time-skip should not be too large as well, because ntp doesn't support large timesteps.

[Marco Santerre]

We use a private box within the firewall to synchronized our server.

Unfortunately that box doesn't belong to my department so I wouldn't be able to tell you the exact cost associated with it.

[Rita C Workman]

Two sites...
One server at each site becomes my master time server is pointed to outside source time server; the remaining servers at each location then point to the in-house master time server to sync to that.

Rita

[Patrick Wallek]

I have 2 HP-UX machines that I point all of my other HP-UX servers to. These 2 machines each sync to 2 outside time sources, though I am thinking of adding 2 or 3 more time sources to each just for the fun of it.

[Elena Leontieva]

What about routers, are they in sync?

[Robert-Jan Goossens]

http://www.oreilly.com/catalog/hardcisco/chapter/ch10.html

You mean using your routers as a ntp server or sync your routers to a ntp server ?

Regards,
Robert-Jan

[Elena Leontieva]

I asked about synchronizing a router with the ntp server.

The issue that we had so far is that we've got SNTP servers (W2K and NT4) and our Cisco router could not query a Windows system. So, it has to be an NTP device.

Elena.

[Marco Santerre]

Though not myself, I think some servers in the midrange area (not HP-UX) are synchronizing with routers and it seems to be working fine.