Best practise for time sync

[ermac]

I am sure this topic has been discussed a few times here, but would like to know what most think the best practise is for syncing Dahua IP cameras' time with a Dahua NVR/XVR's time?

Should the NVR/XVR be set to sync with an NTP and each IP camera also set to sync with an NTP in the camera's own settings?

I find if the NVR/XVR is set to sync with an NTP and a camera is not it can randomly go out of sync with the NVR/XVR's time, and I need to login to the camera and select "sync PC" to correct it's time, so I would imagine syncing with an NTP should solve it permanently.

 

[guykuo]

I have all mine syncing to the same NTP server. A special NTP WAN access was granted in my otherwise closed security camera LAN.
Among the same brand cameras, time remains within 1-2 seconds sync. Across different brands, you will notice the times differ despite same NTP server.

 

[ermac]

Thanks, yeah I noticed the 1 sec difference despite same NTP server! That does irritate me a bit, but good to know it's pretty normal.

 

[redfive]

Usually, my routers act as NTP server for the devices connected to, so, no need to allow unwanted outbound connections

 

[ermac]

Usually, my routers act as NTP server for the devices connected to, so, no need to allow unwanted outbound connections

Don't see how pinging a reliable and trusted NTP server poses any risk to your network though.

 

[iseeker]

Don't see how pinging a reliable and trusted NTP server poses any risk to your network though.

You have to open a port right?

 

[SouthernYankee]

Using NTP uses UDP on port 123. Some routers can act as NTP servers for your network. There is some risk have port 123 open, but the risk is low. Most systems and networks use UDP port 123, so if there were major problems then we would hear about it.

 

[iseeker]

Thanks for the info. I point my cameras to my router as well.

 

[ermac]

Using NTP uses UDP on port 123. Some routers can act as NTP servers for your network. There is some risk have port 123 open, but the risk is low. Most systems and networks use UDP port 123, so if there were major problems then we would hear about it.

Thanks for the info @SouthernYankee.

 

[redfive]

Well, I could allow outbound connections from the NVR/cameras to a couple of NTP servers ip addresses, on UDP 123, but why, since the router itself can act as NTP server ? I mean, I only allow the NVR to contact/initiate connections to some google CIDR's, on tcp 587, for mails, then the NVR/cams VLAN can be contacted only by the trusted VLAN, or via VPN, and nothing more

 

[IAmATeaf]

I use my BI Server as the NTP time source appoint all my cams to it.

 

[teemu81]

On my Dahua devices I activate the ntp on the NVR only, then I check the sync to IPC option on the NVR (activated by default) so the own NVR will syncronize the time with the cameras each X hours. You'll still need to set the cameras on the same GMT than the NVR and activate the DST settings to match the NVR.

 

[HoosierD]

I too use my BI Server and NetTime as the NTP time source for all my cams. Zero open ports in todays world.

 

[DICKNLA]

I am sure this topic has been discussed a few times here, but would like to know what most think the best practise is for syncing Dahua IP cameras' time with a Dahua NVR/XVR's time?

Should the NVR/XVR be set to sync with an NTP and each IP camera also set to sync with an NTP in the camera's own settings?

I find if the NVR/XVR is set to sync with an NTP and a camera is not it can randomly go out of sync with the NVR/XVR's time, and I need to login to the camera and select "sync PC" to correct it's time, so I would imagine syncing with an NTP should solve it permanently.

hello everybody.

does anyone have a good new time server to sync with since clock.isc.org has been canceled. i have tired a few also time.google.com and i am not having any luck. i haven't changed the default port on any camera though.

 

[SpacemanSpiff]

hello everybody.

does anyone have a good new time server to sync with since clock.isc.org has been canceled. i have tired a few also time.google.com and i am not having any luck. i haven't changed the default port on any camera though.

Google "ntp time servers" followed by your country name

i.e. ntp time servers us