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vMX NTP sync

Posted: Fri Apr 14, 2017 12:52 pm
by MicCheck
Need some help with vMX time synchronization.

If I configure the vMX to sync its time with NTP server, then that vMX becomes unresponsive in a minute or two after 'commit'. Reboot does help for another couple of minutes.

Is ther some trick to make NTP-sync stable. IOL-nodes sync perfectly with the same NTP server.
'show ntp status' shows that vMX is "unsychronized".
'monitor traffic' shows a normal NTP exchange between vMX and NTP server.

The NTP server is reachable via em0 (management interface). It is actually within the same directly connected network as vMX. vMX Junos documentation states that it is possible to use NTP on management interface. Junos version is 14.1R4.8.

As far as I remember, there was an option in UNL to sync vMX nodes' time with host and it did solve the issue with unresponsiveness. But I can't find anything like this in EVE.
Is there any way to do that? This will be a simple workaround..

Re: vMX NTP sync

Posted: Fri Apr 14, 2017 10:49 pm
by ramindia
Hi

What is the NTP Server you using, Public one ?
Did your vMX have public reachability ?

R!

Re: vMX NTP sync

Posted: Mon Apr 17, 2017 2:23 pm
by MicCheck
Hi,

I'm using my Synology NAS, which syncs with external public NTP.
It is not a connectivity issue. As I already said, tcpdump (monitor traffic) on vMX shows normal NTP exchange.
There's NTP server's IP in "show ntp associations" and its 'refid' (an IP of upstream NTP server with which my NAS is synced with).

My lab consists of some vMXes and IOL switches. All of them have one interface connected to pnet0, which is bridged to my home network with all the servers and stuff. All servers and lab-devices (virtual) are in the same /24 network.