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New Member

NTP Time Synchronization


i have a 2620 router which is an ntp time server for serevral routers of an isdn wan. I want to configure the router to act as an ntp client and get the time from a time server in the internet. After configuring the router to get the time from a server the router don´t send ntp request packets to the time server.....

I have configured ip name service and the time server is requested by its DNS name. Can anybody tell me why the router doesn´t send ntp requests to the server?!

Thanks a lot


  • Other Network Infrastructure Subjects
New Member

Re: NTP Time Synchronization

Check that the NTP server is a public server.

Check if the server use MD5 authentication.

Check the NTP version so that your router and server match.

Check that your router have the right time, date and year.

Try the use the IP address instead of DNS name.

What is "show ntp stat" and "show ntp ass" tell you?

New Member

Re: NTP Time Synchronization


i have tried everything. I have configured a router which is directly connected to the internet and there it works. If i try it on a router within a lan it´s not possible. The stratum is always 16. The router routes the ntp packets through the proxy server. The is no firewall blocking ntp packets. Why is the startum always 16?! And what is possible to do?!