NTP disconnect issue



  • Hi,

    PFSense is running a NTP service for the network clients on one of the LAN interfaces (192.168.1.1). I have multiple LAN interfaces (192.168.2.1, 192.168.3.1 etc.) on this PFSense box. Each of these LAN networks use the NTP service of PFSense. There are PFSense rules configured on the additional LAN interfaces (192.168.2.1, 192.168.3.1 etc.) to allowed the NTP network traffic to 192.168.1.1 .

    NTP works, all clients, in all LANs can connect and sync their time. But the clients in the additional LAN networks keep randomly disconnecting a few times a day. They reconnect after some time (minutes - hours).

    What can cause this? Network load on the PFSense box?

    Note: I don't want to start the NTP service (as a solution for this issue) on each LAN interface of PFSense as the NTP clients are using a DNS record (ntp.mydomain.tld).

    Regards,
    Sander


  • Rebel Alliance Global Moderator

    So your saying devices on the lan that ntp is actually listening on do not disconnect ever?

    How are you seeing that they disconnect.. is it something in the clients ntp log?  Is their time drifting?



  • Based on the output of 'ntpq -pn' on the client:

    remote          refid              st t when poll reach  delay  offset  jitter

    192.168.1.1  xx.xxx.xxx.xxx      2 u  215 1024  377    0.382  2345.81 1806.01

    Please note the star '*' is missing in front of the NTP server IP-address. This means there is no active sync server (as I understand it correctly).


  • Rebel Alliance Global Moderator

    but your 377 shows that it has not missed queries to it in the last 8 times its asked.. But there is a large offset and your jitter is high..

    From that that output it doesn't show that it can not reach the ntp server, but has not selected it for peer.. You need to find out why this is.. But your reach if stays at 377 shows that every time you query it you are getting a reply.



  • Why don't you just have the NTP server listen on all LAN interfaces? Why only one?