NTP server appliance

[Ira]

Anyone know of a COTS consumer grade (i.e., up to a few hundred dollars in cost) NTP server appliance that sync's via GPS? Something that sits on the LAN and all the LAN-attached devices can sync up their time to it.

I know there are software solutions available, but for something like this, I lean towards a dedicated appliance.

Thanks,
Ira

 

[damage]

ntpd and a seagate dockstar, pogoplug or maybe even a router running dd-wrt? it's still a software solution and will require some work on your end, but it's practically a dedicated appliance

 

[pete_c]

I would like to switch my NTP server (W2003 with a GPS) over to the Dockstar. I've been using a GPS for internal time for a few years now.

How would you configure NTPD to get the time from a serial (via USB) device. I mean I can get serial stuff from the USB port; but what would you do to get the time?

I've seen the threads about getting the one GPS sentence for time sync; etc. Looking for a totally maintainance free setup.

I just want something very simple that broadcasts a stratus X on my network that never fails. Its way overkill to use a Windows server for this function. I currently am not using the outside GPS antenna as it got struck by lightning and no longer works. Instead I use an antenna in the attic and it still sees more than 3 satellites just fine. I am replacing the outside antenna where as I have a dedicated GPS cable to the basement where I could install the Dockstar next to the GPS. I also have an experimental GPS board with output to Bluetooth, USB and RS-232. It is kind of an all in one board with additional pin outs for more accurate time sync; taking the big box "COTs" dedicated box to something as small as one little pc board.

 

[rismoney]

Might I ask what the importance of needing "accurace time" is? I have done a lot of tuning around ntp to obtain ~1ms accuracy. Microsecond is a different animal altogether, and will require PTP or other clock keeping protocols.

Break the problem up into parts-is there an issue in getting the time from a reliable source, distributing time, managing drift on hosts, managing network latency, and/or the overall managing of a distributed clock environment.

Most of the time the issues I see are balancing host based corrections to counteract clock drift typically related to cpu utilization on endpoints. Rarely do I see it really matter if someone is dead on accurate to some other "mothership". Usually it's a LAN problem.

To PeteC - many network switches, like from cisco can be configured to run ntp and can broadcast time. These things are rocks.

 

[pete_c]

Actually my "roots" about my home personal time keeping started at United Airlines. Today I do keep utilizing an internal NTP server and rely less on the internet for the time. Mostly from the router to the switch to the desktop the entire global network was overengineer and fully rendundant for failover. Even the smallest 20-30 (it could have been an engine service facility, airport facility or just city reservations office) station locations would have two routers, two autonomous WAN providers, autonomous failover for power, etc.

With UAL it started as project was related to an old vectoring program that ran on Unix desktops. The GPS placement at the airport was critical. It was the same vendor for the same GPS setup for many years. Honestly the unit looked like a 1955 Cadillac Eldorado with massive shiny chrome bumpers. It was though installed in major global hubs throughout the world. The project was to upgrade the GPS units and unix software utilized for the vectoring application.

On a related project I noticed differences with the routers (Cisco et al) and Switches (variety but mostly Cisco) and DNS servers. Personally I was always picky on the time. It did relate to updates to whatever piece of hardware and kind of coordinated efforts (Initially over 140K user clients at one time).

I really didn't need to do this at home. My FW/Router already had the ability to generate an NTP source. Just did it for fun.

I then decided it would be better to utilize a centralized time internal time base for HQ and do it kind of at a reasonable cost. The building I was in was 3 stories and the roof had reminants of an old building to building com setup (antennas etc). I mounted a small nautical like GPS antenna customized a bit and put it on a mast by the elevator "hut" on the roof; actually climbing and doing it myself (kind of picky this way). The RF cable ran down to the basement server room which was maybe 30 feet or so below ground level. I used an amplifier to get a full satellite view and it worked fine. It did go to a dedicated box which then became the main internal time server base for the routers, switches and DNS servers. I am not sure if its being utilized today as it was done sometime in the 2000's.

At home I've done similiar on a much smaller scale with the GPS antenna on the roof with an RF cable/amplifier going to the basment NTP receiver serially connected to an NTP box. If I could take all of it to just the Dockstar / GPS receiver I could mount it next to the Leviton panel.

 

[Ira]

Hours of Googling led me to http://css-timemachi.../B002RC3Q4Q.htm. Looks like what I need. Price is about right. A couple of good, recent reviews on Amazon.

Comments?

Thanks,
Ira

 

[pete_c]

Very reasonably priced Ira compared to the older thousand dollar units. BUT you can roll your own for much less than $100 these days.

The GPS board pictured about is like $30 (on Ebay) and see's about 6 satellites inside of the house pointed to a window 6 feet away. You only need three for an accurate time sync. The Ebay special comes with an antenna but no PS. I use an IPOD type USB wall jack adapter for it. The onboard outputs allows for some very accurate syncing. You only look at one sentence (time). It spits out way more than just NMEA sentences; lots of diagnostic stuff. You can talk to this one with a basic command line structure, customize it such that it only talks 1-2 sentences and change the baud rates on it from the typical (4800). Its kind of a custom job for playing with.

I also have a couple of very old Trimbles. Very custom surplus in very solid small metal cases with just an RS-232 / and two 9 pin serial ports. Custom Trimble firmware and meant to be used in pairs on one vehicle. Rugged little boxes. Think I paid only $10 for these. No documentation with them. They work fine spitting out NMEA modified sentences. You could roll a truck over them and it wouldn't bend the case. The do also sell little GPS's the size of your thumb (Motorola) with just TTL output which you would have to convert some.

First setup for me years ago was using a free well known application called Tardis. It has the option of connection to a GPS. It also has the option to broadcast NTP on your network. So your costs are just for the hardware. A $30 GPS test board. It comes with an antenna and can be powered from the USB port. So your up front cost would only be $30. The Tardis program has been around quite a long time so it'll run on just about anything. It runs as a service silently in the backround. Its not fancy; its just a simple application. There are many "paid for" applications that do exactly the same with many "bells and whistles" and the cost of these programs is similiar to the unit you posted above.

19 Interpreted sentences

$GPBOD - Bearing, origin to destination
$GPBWC - Bearing and distance to waypoint, great circle
$GPGGA - Global Positioning System Fix Data
$GPGLL - Geographic position, latitude / longitude
$GPGSA - GPS DOP and active satellites
$GPGSV - GPS Satellites in view
$GPHDT - Heading, True
$GPR00 - List of waypoints in currently active route
$GPRMA - Recommended minimum specific Loran-C data
$GPRMB - Recommended minimum navigation info
$GPRMC - Recommended minimum specific GPS/Transit data
$GPRTE - Routes
$GPTRF - Transit Fix Data
$GPSTN - Multiple Data ID
$GPVBW - Dual Ground / Water Speed
$GPVTG - Track made good and ground speed
$GPWPL - Waypoint location
$GPXTE - Cross-track error, Measured
$GPZDA - Date & Time

Here is a live view of one of three GPS's that I am playing with.
This one the GPS (very old Garmin) and antenna are between rafters in the attic.

$GPGLL,4134.4410,N,08800.6296,W,213518.875,A*28
$GPGGA,213518.87,4134.4410,N,08800.6296,W,1,08,0.9,00234,M,,,,*3C
$GPRMC,213518.87,A,4134.4410,N,08800.6296,W,00.0,000.0,191111,02.,W*69
$GPGSA,A,3,02,29,21,05,25,26,30,15,,,,,1.8,0.9,1.6*3E
$GPGSV,3,1,11,29,67,264,45,05,55,049,52,26,51,117,44,15,37,170,49*73
$GPGSV,3,2,11,02,25,101,40,21,25,295,36,18,13,242,,30,10,300,38*73
$GPGSV,3,3,11,25,08,224,39,08,02,064,,07,01,037,,,,,*42

 

[Ira]

I ordered the NTP server appliance I linked to above. With the sales they have going on, total price, including S&H, was about $246.

According to the manufacturer, the only noticeable indication that the time server loses its GPS lock (and therefore can't provide the time) is a flashing LED on the front panel. I expect that this thing will not be quite as reliable as one of the internet NTP servers (and won't be monitored 24x7), so I need to come up with another way to notify me if it loses GPS lock. A simple email will do, since it's not that critical unless it loses it for a long time. My plan is to see if I can get a CQC driver that will poll it every few minutes. Supposedly, it will respond with a specific code if it doesn't have GPS lock.

 

[BraveSirRobbin]

I ordered the NTP server appliance I linked to above. With the sales they have going on, total price, including S&H, was about $246.

According to the manufacturer, the only noticeable indication that the time server loses its GPS lock (and therefore can't provide the time) is a flashing LED on the front panel. I expect that this thing will not be quite as reliable as one of the internet NTP servers (and won't be monitored 24x7), so I need to come up with another way to notify me if it loses GPS lock. A simple email will do, since it's not that critical unless it loses it for a long time. My plan is to see if I can get a CQC driver that will poll it every few minutes. Supposedly, it will respond with a specific code if it doesn't have GPS lock.

Just a thought, but you can monitor that flashing light with your home automation system.

 

[Ira]

Probably, but that would require additional hardware for me to buy. I think a CQC driver (or even a "standalone" application) shouldn't be too difficult. It's just a TCP/IP connection, and it doesn't need to do anything with the returned info, other than recognize the flag that the data is invalid (lost GPS lock) and send out a notification.

 

[Ira]

An upate on the TM1000A...

It was delivered about ten days ago. Installation and setup were easy enough. I'm able to get a good GPS lock from inside my home in a room with no windows. Sometimes it takes a minute or two to get the GPS lock, but once it does, I've never seen it lose it.

Initial usage was hit and miss. My Netgear router sync'ed up with no problem. My Windows 7 PC's were not able to sync up using the built-in NTP client, but then again, I had problems with them trying to sync up with an Internet NTP server, too. So I tried several NTP client/server app's (Tardis 2000, Clockwatch, YATS32, etc.) with varying degrees of succes. They all worked some of the time, but they all failed to sync a few times, too. I have a couple of Synology NAS boxes that could sync with an Internet NTP server, but failed every time with the TM1000A.

I contacted the manufacturer with my observations, and provided them some documentation from the NTP client app(s) logs. Yesterday, they sent me a firmware update. Simple enough to install. Firmware upgrade tool uploads the new firmware via the LAN connection, so no need for a serial connection, etc. So far, I've tested it with my Netgear router (to make sure it still works), a Windows 7 Pro built-in client (w32time?), and one of the Synology NAS boxes. All sync'ed up correctly. Looks to be working well.

I don't know (and didn't ask) if this is a relatively new product. It seems like the problems I saw would have been reported before if it has been out for a while. Doesn't really matter to me, though, and I am happy with the purchase. Pretty cool little device.

Regarding my previous comments about writing a CQC driver to detect that the TM1000A lost the GPS lock...some of the add-on NTP apps can send out email notifications of sync failures, and they can be set to do a sync as often as every minute. That's good enough notification for me, at least for now.

 

[pete_c]

Ira,

Thank-you for the info. I've always been a bit "overboard" with time sync on my network and never did see a commercially sold product which was optimally priced for the consumer market. It was basically a DIY thing.