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    dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down

    Scheduled Pinned Locked Moved DHCP and DNS
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    • R
      ryanrozich @jimp
      last edited by

      looks like this file does not exist /var/etc/newsyslog.conf.d/pfSense.conf - so looks like you are right. However I dont know how to restore that file. Replies below:

      @jimp said in dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down:

      Did you maybe disable log rotation somehow? It's enabled by default and would normally prevent that from happening.

      Look in /etc/crontab and see if you see a line like this:

      */1 * * * * root /usr/sbin/newsyslog

      ✔ yes, thats there

      Now look at the configuration for newsyslog in /var/etc/newsyslog.conf.d/pfSense.conf:
      It should have a line for every log file, including the DHCP log file, for example:

      /var/log/dhcpd.log root:wheel 600 7 500 * C

      That file does not exist, that directory is empty - see below:

      [23.05-RELEASE][admin@pfSense.rozich.com]/root: ls /var/etc/newsyslog.conf.d/
      [23.05-RELEASE][admin@pfSense.rozich.com]/root:
      

      Then look at Status > System Logs, Settings tab and check the Log Rotation Options section. What exactly is set in the three options in that section?

      See below - note that the values in the first and third boxes are in grey (probably indicating the default values for those fields)

      0c2bbb1b-12a2-4112-a39d-f95eade5e051-image.png

      R 1 Reply Last reply Reply Quote 0
      • R
        ryanrozich @ryanrozich
        last edited by

        @ryanrozich Sounds like first order of business is to get log rotation turned on, if I could get instructions for that I'd be grateful.

        Separately, does it seem strange that its been less than 24 hours since I manually truncated my log files yesterday and I am already back up to 7GB usage (of 13GB on my netgate 6100) from dhcpd? This is my home network - family of 5, I work from home - 3 kids with ipads and an array of iot devices (set top box, ring cameras, etc).

        I have not intentionally turned off log rotation, so I'm not sure if it was ever on. Could this be some problem with one of my devices on the network? or some issue with my recent pfsense+ update?

        GertjanG 1 Reply Last reply Reply Quote 0
        • jimpJ
          jimp Rebel Alliance Developer Netgate
          last edited by

          I suspect there is a bug in there similar to https://redmine.pfsense.org/issues/14283 where it isn't doing rotation because the log settings are empty (all at defaults and the entire section is missing from the config.xml file).

          If you make some non-default change to the log settings, such as changing the compression to 'none' (which is probably a good move anyhow), that should kick it in.

          As to why DHCP is logging so much, that is very odd but it's hard to say why without knowing what is in the log. Something on your local network could be hitting the service hard even with very few devices. It just takes one broken thing going nuts to cause trouble.

          Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

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          • GertjanG
            Gertjan @ryanrozich
            last edited by

            @ryanrozich said in dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down:

            and I am already back up to 7GB usage

            Well .... don't keep us waiting : what is happening ?
            Have a look at the last 300 ~ 500 lines of that file.

            tail -n 500 /var/log/dhcpd.log
            

            To follow it

            tail -f /var/log/dhcpd.log
            

            Hit Ctrl-C to end.

            What kind of lines are added ?

            My guess :
            Some device uses a Wifi connection that is on the edge of 'out of reach' so every time the Wifi connections comes up again, dhpc is activated, and loads of DHCP transactions are logged.
            Or, some 'made in ****' device has pretty broken dhcp client that chain guns the DHCP server.

            Solution : wast-bin the offending device and done.

            Major side effect : the DHCP log fills up fast.
            If also issue 14283 (see Jimp's post above) is in play, the the file system fills up and that breaks everything.

            No "help me" PM's please. Use the forum, the community will thank you.
            Edit : and where are the logs ??

            R 1 Reply Last reply Reply Quote 0
            • jimpJ
              jimp Rebel Alliance Developer Netgate
              last edited by

              Confirmed my suspicion and reproduced it in a lab system:

              https://redmine.pfsense.org/issues/14517

              I also pushed a fix ( 892de1ecdaa23b164f6b2a2251d7538eee2199ea ).

              But the simplest workaround is to save on the syslog settings as I mentioned. No need to patch anything if you do that, it will just start to work immediately.

              Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

              Need help fast? Netgate Global Support!

              Do not Chat/PM for help!

              R 1 Reply Last reply Reply Quote 1
              • R
                ryanrozich @Gertjan
                last edited by

                @Gertjan

                This is what the tail of that log looks like

                424ad0fb-2bfd-4a8c-b2c7-120562bc96e1-image.png

                1 Reply Last reply Reply Quote 0
                • R
                  ryanrozich @jimp
                  last edited by

                  @jimp Thank You! I just truncated the logs again and then made the change from bzip to none compression. I'll keep an eye on it

                  Does this mean that in a future pfsense release there should be a fix?

                  johnpozJ jimpJ GertjanG 3 Replies Last reply Reply Quote 0
                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @ryanrozich
                    last edited by johnpoz

                    @ryanrozich you have a problem child there - that box ending in b54f how many times is he going to ask for renew IP?

                    No wonder your logs are HUGE..

                    Looks from that log that all happened in 1 second?

                    An intelligent man is sometimes forced to be drunk to spend time with his fools
                    If you get confused: Listen to the Music Play
                    Please don't Chat/PM me for help, unless mod related
                    SG-4860 24.11 | Lab VMs 2.8, 24.11

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                    • jimpJ
                      jimp Rebel Alliance Developer Netgate @ryanrozich
                      last edited by

                      @ryanrozich said in dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down:

                      @jimp Thank You! I just truncated the logs again and then made the change from bzip to none compression. I'll keep an eye on it

                      Does this mean that in a future pfsense release there should be a fix?

                      Yes, future releases will have the fix.

                      Remember: Upvote with the 👍 button for any user/post you find to be helpful, informative, or deserving of recognition!

                      Need help fast? Netgate Global Support!

                      Do not Chat/PM for help!

                      1 Reply Last reply Reply Quote 0
                      • GertjanG
                        Gertjan @ryanrozich
                        last edited by Gertjan

                        @ryanrozich said in dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down:

                        Does this mean that in a future pfsense release there should be a fix?

                        Why wait if you can have a good permanent solution right now ?
                        The patches come from the official source.

                        44bcea67-fceb-43fb-aff4-967154ec577e-image.png

                        The first patch = https://github.com/pfsense/pfsense/commit/892de1ecdaa23b164f6b2a2251d7538eee2199ea.patch

                        Second patch = https://github.com/pfsense/pfsense/commit/77e168861ba43b3d6290df07fc04481c09174b28.patch

                        No "help me" PM's please. Use the forum, the community will thank you.
                        Edit : and where are the logs ??

                        johnpozJ 1 Reply Last reply Reply Quote 0
                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @Gertjan
                          last edited by

                          So fixing log rotation issues is only going to mask the issue of that one client constantly asking for renewal.

                          An intelligent man is sometimes forced to be drunk to spend time with his fools
                          If you get confused: Listen to the Music Play
                          Please don't Chat/PM me for help, unless mod related
                          SG-4860 24.11 | Lab VMs 2.8, 24.11

                          R 1 Reply Last reply Reply Quote 0
                          • R
                            ryanrozich @johnpoz
                            last edited by

                            @johnpoz agreed. I switched my printer from wired to wireless networking and that seemed to fix that issue.

                            However if this hadn’t taken down my home network I wouldn’t have known about it. Is there any alerting that I could enable in pfsense that would warn me of problems like this?

                            GertjanG 1 Reply Last reply Reply Quote 0
                            • GertjanG
                              Gertjan @ryanrozich
                              last edited by

                              @ryanrozich said in dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down:

                              from wired to wireless networking

                              That's original, as normally, it's the wireless connection that has a very limited (bad) connection, so it get reconstructed again and again, and that introduces a DHCP sequence on every 'link up'.

                              If a wired connection does this : I'll bet you have a bad NIC on one side, or a bad cable.

                              Or the printer has a very bad DHCP client implementation, like : forcing the the DHCP lease duration to 10 seconds or so.

                              @ryanrozich said in dhcpd.log file is ~10GB, filling my disk up every couple days and taking my network down:

                              However if this hadn’t taken down my home network I wouldn’t have known about it. Is there any alerting that I could enable in pfsense that would warn me of problems like this?

                              😊

                              That is actually the reason why pfSense is not some AI driven device that you power up, hook up and walk away. Like a switch.
                              pfSense needs the human type of admin, in this case : you. And 99 % of the time you won't be looking at the dashboard, but you're somewhere in the Status menu.
                              The most favorite one is all the log files.
                              And no, I'm not kidding 😊

                              But I have a tip : when you add a 'new' device to your network, you should have a look at your log files (System, DHCP, DNS) a couple of times.
                              Things can always go bad, cable get cut, wifi gets destroyed by the new AP the neighbor bought (or the new micro wave that "works just fine with the door open").

                              No "help me" PM's please. Use the forum, the community will thank you.
                              Edit : and where are the logs ??

                              1 Reply Last reply Reply Quote 1
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