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    [Solved] Am I really using pfSense as NTP server ...?

    Scheduled Pinned Locked Moved General pfSense Questions
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    • JKnottJ
      JKnott @furom
      last edited by

      @furom

      Maybe you have a client that's asking too frequently. I've been running NTP servers for many years, even before I used pfSense, and have never seen that.

      The way it works is your server syncs with whatever servers you select and then makes the time available to clients. You can have multiple servers and that provides better accuracy and redundancy. You should have at least 3 sources and some say as many as 5 or 6. You don't want 2, as if one goes bad and produces the wrong time, your server won't know which one and will cut them both off. I use 3 stratum 1 servers and 3 stratum 2.

      Use Packet Capture to see where those KoD packets are being sent.

      PfSense running on Qotom mini PC
      i5 CPU, 4 GB memory, 32 GB SSD & 4 Intel Gb Ethernet ports.
      UniFi AC-Lite access point

      I haven't lost my mind. It's around here...somewhere...

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      • F
        furom @JKnott
        last edited by

        @JKnott said in Am I really using pfSense as NTP server ...?:

        @furom

        Maybe you have a client that's asking too frequently. I've been running NTP servers for many years, even before I used pfSense, and have never seen that.

        The way it works is your server syncs with whatever servers you select and then makes the time available to clients. You can have multiple servers and that provides better accuracy and redundancy. You should have at least 3 sources and some say as many as 5 or 6. You don't want 2, as if one goes bad and produces the wrong time, your server won't know which one and will cut them both off. I use 3 stratum 1 servers and 3 stratum 2.

        Use Packet Capture to see where those KoD packets are being sent.

        Thanks, but that's just it.. If any of my clients ask pfSense too much it shouldn't generate KoD's from an external NTP...? What I'd expect is pfSense responding locally, no?

        RobbieTTR 1 Reply Last reply Reply Quote 0
        • RobbieTTR
          RobbieTT @furom
          last edited by

          @furom The pfSense GUI will show you when and how often it is polling from the sources and if they are actually available:

           2023-06-06 at 13.57.00.png

          You can go deeper than this but it will probably answer your question.

          ☕️

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          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            Yes, ntpd should just respond to clients locally. That should not generate additional external queries.

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            • F
              furom @stephenw10
              last edited by furom

              @stephenw10 said in Am I really using pfSense as NTP server ...?:

              Yes, ntpd should just respond to clients locally. That should not generate additional external queries.

              So I could be forwarding queries somehow... I certainly don't intend to, I would be very happy keeping clients in sync with pfSense. Does my rule for catching NTP look alright? Before that I had all sorts of NTP requests blocked, so thought a NAT was the way to go, but perhaps pfSense is not what actually responds in my case?

              NollipfSenseN 1 Reply Last reply Reply Quote 0
              • F
                furom @RobbieTT
                last edited by

                @RobbieTT Thanks :) What I am concerned about is if my clients are in fact served by pfSense, or if my NAT is not enough to contain local NTP traffic...

                RobbieTTR 1 Reply Last reply Reply Quote 0
                • RobbieTTR
                  RobbieTT @furom
                  last edited by

                  @furom Understood. Are you going to post your Status / NTP table?

                  ☕️

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                  • F
                    furom @RobbieTT
                    last edited by

                    @RobbieTT Here it is, it looks a lot like yours I suppose
                    5081d01a-69c3-4f49-98fa-f634b38a2fe6-image.png

                    RobbieTTR 1 Reply Last reply Reply Quote 0
                    • NollipfSenseN
                      NollipfSense @furom
                      last edited by NollipfSense

                      @furom said in Am I really using pfSense as NTP server ...?:

                      So I could be forwarding queries somehow... I certainly don't intend to,

                      If you look at your firewall rule, in the comment you stated that indeed to "redirect NTP to pfSense." So, that implied it was by design. Here is mine also as well as firewall rule:

                      Screenshot 2023-06-06 at 8.28.28 AM.png

                      Screenshot 2023-06-06 at 8.31.45 AM.png

                      pfSense+ 23.09 Lenovo Thinkcentre M93P SFF Quadcore i7 dual Raid-ZFS 128GB-SSD 32GB-RAM PCI-Intel i350-t4 NIC, -Intel QAT 8950.
                      pfSense+ 23.09 VM-Proxmox, Dell Precision Xeon-W2155 Nvme 500GB-ZFS 128GB-RAM PCIe-Intel i350-t4, Intel QAT-8950, P-cloud.

                      F 1 Reply Last reply Reply Quote 0
                      • RobbieTTR
                        RobbieTT @furom
                        last edited by

                        @furom It's not looking that healthy. One active peer is good but there are no other NTP servers with "Candidate" status.

                        Has it recently been restated?

                        ☕️

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                        • F
                          furom @RobbieTT
                          last edited by

                          @RobbieTT Yes, I have been fiddling with it, so probably why

                          1 Reply Last reply Reply Quote 0
                          • F
                            furom @NollipfSense
                            last edited by

                            @NollipfSense said in Am I really using pfSense as NTP server ...?:

                            @furom said in Am I really using pfSense as NTP server ...?:

                            So I could be forwarding queries somehow... I certainly don't intend to,

                            If you look at your firewall rule, in the comment you stated that indeed to "redirect NTP to pfSense." So, that implied it was by design. Here is mine also:

                            Screenshot 2023-06-06 at 8.28.28 AM.png

                            Well, yes. I wrote the rule with intention to send all traffic to pfSense. I believe that part to work fine, but what actually responds to it, if it is pfSense or some external NTP is the question as I did get KoD packets from external NTP servers

                            RobbieTTR 1 Reply Last reply Reply Quote 0
                            • stephenw10S
                              stephenw10 Netgate Administrator
                              last edited by

                              It's ntpd that responds locally. There is no forwarding ntp queries.

                              You should be able to see states for ntp queries that are somehow missing your redirect. If they exist.

                              The only other option might be that clients are using one of the encrypted ntp types to connect externally. But if that was the case you probably wouldn't see the KoD packets. Not something I've ever looked into though.

                              Steve

                              F RobbieTTR 2 Replies Last reply Reply Quote 0
                              • RobbieTTR
                                RobbieTT @furom
                                last edited by

                                @furom ntpq is polling at the correct rate, which is at the default of 64 seconds, but it will relax to a slower rate if/when it is happy.

                                At this point I think we are looking at your ntpq instance issuing KoD at a LAN client or clients. This may be due to an excessive request rate or simply due to ntpq not being happy about its own status.

                                ☕️

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                                • F
                                  furom @stephenw10
                                  last edited by

                                  @stephenw10 said in Am I really using pfSense as NTP server ...?:

                                  It's ntpd that responds locally. There is no forwarding ntp queries.

                                  You should be able to see states for ntp queries that are somehow missing your redirect. If they exist.

                                  The only other option might be that clients are using one of the encrypted ntp types to connect externally. But if that was the case you probably wouldn't see the KoD packets. Not something I've ever looked into though.

                                  Steve

                                  Ok. Well, it was just a bit of a mystery, probably not something to dig much deeper in. Thanks all for the feedback and insights. :)

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                                  • F
                                    furom @RobbieTT
                                    last edited by

                                    @RobbieTT Well, if so, shouldn't these KoD packets originate from pfSense? Anyhow, I haven't seen any new ones since yesterday, so guess whatever the issue was is gone for now at least. Thanks :)

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                                    • RobbieTTR
                                      RobbieTT @stephenw10
                                      last edited by

                                      @stephenw10 said in Am I really using pfSense as NTP server ...?:

                                      The only other option might be that clients are using one of the encrypted ntp types to connect externally. But if that was the case you probably wouldn't see the KoD packets. Not something I've ever looked into though.

                                      Steve

                                      Steve, your instinct is correct as an encrypted ntp would not return a KoD. It would either drop or, more helpfully, issue a CRYP response.

                                      ☕️

                                      1 Reply Last reply Reply Quote 1
                                      • V
                                        viragomann @furom
                                        last edited by

                                        @furom
                                        Did you forward NAT request to your pfSense on local interfaces?

                                        F 1 Reply Last reply Reply Quote 1
                                        • F
                                          furom @viragomann
                                          last edited by

                                          @viragomann Yes, I have rules like this in place on them
                                          b5c5dbcb-d510-4644-bcb7-9ed039619ff9-image.png

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                                          • V
                                            viragomann @furom
                                            last edited by

                                            @furom
                                            No, that is a simple pass rule.
                                            I was asking if you redirect all NTP requests to pfSense.

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