What happens to any recordings when Windows syncs time with a NTP server?

[luder888]

I'm just curious about how this works...

When Windows syncs with the NTP server to adjust the time, what happens to the recordings within the duration of the adjustment? I know Windows 10 syncs its time on a weekly basis, and my machine can sometimes be off by almost 1 minute. What happens to that 1 minute of recordings in Blue Iris?

Let's say my machine's time is adjusted from 01:12:30 to 01:11:30. Does that minute simply get lost?

 

[bp2008]

These are the kinds of problems that give programmers nightmares. That and daylight savings.

I have no idea what happens, but if you really want to find out you could test it by manually setting your clock back and forward, and let us know the results. It is bad practice (for programs) to use the current date and time for important application logic, so there is a good chance Blue Iris won't be doing that and the worst you'll see is some clips appearing out of order as you mess with the time.

You may also be interested in running NetTime which you can get from NetTime - Network Time Synchronization Tool. It is a little service that will keep your computer's clock up to date far more reliably and more often than Windows will on its own. Like every 12 hours. But the main benefit of NetTime is you can have it act as a network time server which your cameras can use to keep their own internal clocks accurate. That way you can have each camera embed its own timestamp and it will actually be there when you record direct to disk in Blue Iris.

 

[luder888]

These are the kinds of problems that give programmers nightmares. That and daylight savings.

I have no idea what happens, but if you really want to find out you could test it by manually setting your clock back and forward, and let us know the results.

You may also be interested in running NetTime which you can get from NetTime - Network Time Synchronization Tool. It is a little service that will keep your computer's clock up to date far more reliably and more often than Windows will on its own. Like every 12 hours. But the main benefit of NetTime is you can have it act as a network time server which your cameras can use to keep their own internal clocks accurate. That way you can have each camera embed its own timestamp and it will actually be there when you record direct to disk in Blue Iris.

I was actually researching on how to update my server's time more frequently, but your solution seems to be better since it can keep all the camera's time in sync. Funny you mentioned about daylight savings being a nightmare. I've heard some crappy NVR simply overwrites the hour during daylight savings, and there's actually an increased number of burglaries during that hour. Luckily I live in Arizona where we don't do daylight savings.

 

[luder888]

So like you said I manually set the clock back 5 minutes to see what happens.

- In timeline view, the 5 minutes of recording disappeared.
- However, if you open the clip file by itself, everything is there. There's just a 5 minute offset between the NVR timestamp and BI timestamp.

 

[tangent]

sounds about right. There are still some payroll systems and time clocks out there that fuck up the dst change, but there aren't that many people working at 2am.

 

[VRC]

These are the kinds of problems that give programmers nightmares. That and daylight savings.

I have no idea what happens, but if you really want to find out you could test it by manually setting your clock back and forward, and let us know the results. It is bad practice (for programs) to use the current date and time for important application logic, so there is a good chance Blue Iris won't be doing that and the worst you'll see is some clips appearing out of order as you mess with the time.

You may also be interested in running NetTime which you can get from NetTime - Network Time Synchronization Tool. It is a little service that will keep your computer's clock up to date far more reliably and more often than Windows will on its own. Like every 12 hours. But the main benefit of NetTime is you can have it act as a network time server which your cameras can use to keep their own internal clocks accurate. That way you can have each camera embed its own timestamp and it will actually be there when you record direct to disk in Blue Iris.

This is exactly what I've been looking for, have a few systems with cameras on separate subnet and no internet access, so want them to sync time with BI server.
I first tried this which I got to work on one machine but not the next, so kept searching.
Anyway, can't seem to get this working so far, cameras say fail to connect to server. Any settings I'm missing? Still port 123 to act as time server? Thanks.

 

[bp2008]

Port 123 and I believe it is UDP protocol only. You may need to open this in Windows firewall.

 

[VRC]

Port 123 and I believe it is UDP protocol only. You may need to open this in Windows firewall.

Ya I just disabled the firewall to make sure that wasn't my problem, but still no luck. You have this working?