NTP Issue

Hello,

I was hoping to get some advice from anyone who has set up NTP on a network. I have changed the way that the time is synchronized on the network. My aim is bring the Cisco phones and PC's completly in sync. To do this I'm using a cisco core router to to sync with a time server on the internet this is working. 2nd part is to point Cisco call manager at the Core router to enable the phones to sync their time this is also working. Now the bit that is not working is getting the domain conrtrollers to sync with the core cisco router. From the DC I have tried connecting via telnet on port 123 and this does not work. There are no access lists that would prevent this communication. Its as if the core router is not listening on port 123 and therefor the DC cannot sync.

The command i used on the router was just ntp server (time server address) Does anyone know if I need to do anymore than this. Is their a command to turn the router on so that its listens on port 123??

If anyone has any advice that would be much appreciated

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Comments

tiersten

NTP uses UDP so you can't telnet to that port.

You want ntp master <stratum>

cjthedj45

tiersten wrote: »

NTP uses UDP so you can't telnet to that port.

You want ntp master <stratum>

Thanks Tiersten. I have tried searching through the command lists and I cannot see an NTP master command anywhere. I have done some digging on Ciscos website it states that to make the router listen for NTP traffic you need to enable client broadcast on the interface. I have enabled this on the Vlan interface that I have pointed the domain controller to. However the pcs are still out of sync. Do you know of anyway to test of the domain controllers are actually synching with the router??