NTP client possible bug?!?!

RouterOS General
1

Hi, I’ve just noticed something I want to share.. I use 5 Dahua IP cameras for my CCTV, my IP cams and windows PC’s get its time from the same server, and so does the mikrotik routers… I’ve noticed on mikrotik there is a 4~5sec difference on the clock… Mikrotik is a couple of seconds ahead of all my other devices, they all the same in seconds but only mikrotik differ… why would this be?

I’ve got a couple of routers running, I use ROS v6.44.6 and v6.47.9… both ROS versions does the exact same thing with the 4sec ahead vibe going on!!!

2

Are you getting NTP time on your Mikrotik routers through DHCP or really from NTP server (like pool.ntp.org) ?
I also noticed the former method sometimes gives a difference.
The second method is always spot on. It’s one of the things I standard configure when getting a new device.

If the second method, are you sure all devices (camera’s and routers) sync to the same server ? How do you know ?

3

Are you getting NTP time on your Mikrotik routers through DHCP or really from NTP server (like pool.ntp.org) ?
I’m using this route: “really from NTP server (like pool.ntp.org)”

If the second method, are you sure all devices (camera’s and routers) sync to the same server ? How do you know ?
Yes, I’m sure…I’ve set them all manually myself

4

Where you read the clock? On the video?
Some seconds of differencies can be possible, because the image is processed before you can seee it on video…

5

Weird …
I just checked: Synology NAS to NTP server, PC to NTP server, Mikrotik Hex to NTP server.
All the exact same time, not a bit of difference (not that I can see right away).

Can you do /system ntp client print and provide the result ?

EDIT: rextended has got a point there …

6

enabled: yes
mode: unicast
primary-ntp: 41.73.40.248
secondary-ntp: 0.0.0.0
dynamic-servers:
status: started


I’m using ntp1.neology.co.za everywhere…

7

Have you read my post?

8

because the image is processed before you can seee it on video…
nope, I’m running live, direct from the cameras

See attachment

Capture.JPG
Capture.JPG648×357 65.9 KB

9

If status is started the NTP server do not provide sync.
Only when NTP Client is status: synchronized NTP Server provide the right time.

10

I’ve rebooted the router and then did the print out command… my bad

11

Why don’t you use something that actually works then, instead of whatever this thing is?

12

Because this:

I’m using ntp1.neology.co.za everywhere

Both neology servers behave as if they are down.

These work:
ntp.is.co.za (Johannesburg)
ntp2.is.co.za (Cape Town)

Very bad idea “hardcode” DNS or IP not under own control…

13

I found the issue… that ntp1.neology.co.za server seems to be messedup!! :open_mouth:

I used another server, however its 4sec ahead, but now everything is working perfect!!

14

http://www.time.org.za/
Yip, I used ntp.is.co.za now… 100% working without any issues

Both neology servers behave as if they are down.
100% correct … dammmm I just realized that now..

15

Glad you found the problem.
I always use pool.ntp.org, you can specify further down with country code.

Or like this:

0.pool.ntp.org
1.pool.ntp.org
2.pool.ntp.org
3.pool.ntp.org

It will look for the closest server in your region.

16

What do you mean by this?

17

Ive been using the servers found under http://www.time.org.za/ for ages now.. for NTP clients…
only the neology have the wrong time!!!.. omw they messedup!! and Ive been using them for ages now :confused:

18

It is often not really a good idea to search for NTP servers on some listings, then statically configure them in a router and not really monitor it.
The NTP server may quit at any time, it may serve incorrect time, it may not like you using it and block your IP, etc.

Only include NTP servers that you know to work OK (e.g. you run them yourself or your ISP advertises them as available for their users), or else use pool.ntp.org to automatically select an NTP server that is being monitored and known to be OK.
Unfortunately you can still have problems because the pool.ntp.org name is probably resolved only at boot and not again when the server does not respond, so you would need to reboot the router in that case.
(I did not research that in the case of MikroTik routers because I run my own NTP servers and use those, but this is a problem in many devices that use pool.ntp.org)