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    Kernel: kern.maxfiles limit exceeded by uid 65534, please see tuning(7)

    Scheduled Pinned Locked Moved General pfSense Questions
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    • P
      petr
      last edited by

      Same problem here. Clean embedded install, here is what I got in a config file.

      dnsmasq[37691]: failed to read /etc/resolv.conf: Too many open files in system
      kernel: kern.maxfiles limit exceeded by uid 65534, please see tuning(7).
      

      The system was running for only around a week. I rebooted quickly as I needed to restore functionality. Approx. an hour after reboot, the stats are following:

      ...
         47 sh
       186 php
       214 filterdns
       226 ipfw-classifyd
      

      Will monitor progress and post an update later today.

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      • P
        petr
        last edited by

        After 5 hours of uptime, the stats are following:

         712 filterdns
         752 ipfw-classifyd
        

        Which leads me to believe that this is going to grow until it just cannot, which leads me to more important question - what can I do to mitigate this?

        I am really not running that complex setup - 2xWAN with rules to direct traffic to each + VPN client connection going out. Not that many hostnames either - below 10.

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        • P
          petr
          last edited by

          The numbers seem to be growing, now at:

          
          ...
          1072 filterdns
          1106 ipfw-classifyd
          

          I think this could be related to this: https://forum.pfsense.org/index.php?topic=42991.0

          The number of open files seem to be increasing after every filter reload, which is now every 15m. Although I do not have any schedules set, it still gets reloaded every 15m.

          In any case - it seems to me that  ipfw-classifyd/filterdns do not respond correctly to the HUP signal being sent to them and re-create any temp files they had before for the previous config for the new one… which is not a sustainable approach.

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          • S
            silvertip257
            last edited by

            @petr:
            While this doesn't necessary help you, I got filterdns to stop consuming file handles when I removed the domain name from my IPSec VPN tunnel configuration.

            I expect the increasing number of file handles open by filterdns was a result of Racoon (IPSec daemon) rekeying and what not.

            Of course that thread <0> on the pfsense forum tells of the other problems I'm noticing.

            <0> https://forum.pfsense.org/index.php?topic=81121

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            • P
              petr
              last edited by

              @silvertip257:

              @petr:
              While this doesn't necessary help you, I got filterdns to stop consuming file handles when I removed the domain name from my IPSec VPN tunnel configuration.

              I expect the increasing number of file handles open by filterdns was a result of Racoon (IPSec daemon) rekeying and what not.

              Of course that thread <0> on the pfsense forum tells of the other problems I'm noticing.

              <0> https://forum.pfsense.org/index.php?topic=81121

              Thank you for the suggestion! Sadly, I am not running IPSec thus have nothing to switch-off.

              The filterdns is now at 1118 open files after 1 day, 20 hours.

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              • P
                petr
                last edited by

                Found a workaround - at least I think so, the number of open files has not grown for a few days.

                To cut long story short, I've found out that the number of open files grows in correlation with gateway down alarms in my logs. This lead me to conclude that an unstable connection on one of the VPNs caused frequent alarms and subsequent reloads. As I was not using the alarms to do anything useful, I've simply disabled them for that connection - and voila, open file count stopped growing.

                However, I still believe that there is a problem - in my opinion, having an alarm avery 10m should not be something that would destabilise the router, or lock it up as it does for me!

                What do you think guys?

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                • P
                  phil.davis
                  last edited by

                  Here are my numbers on a production 2.1.5 system that has been up for 7 days:

                     2 kernel
                     2 md0
                     2 md1
                     3 init
                     6 awk
                     7 login
                     7 rrdtool
                     8 apinger
                     8 cron
                     9 fstat
                     9 sudo
                    14 check_reload_status
                    14 devd
                    14 logger
                    15 dnsmasq
                    15 sh
                    16 inetd
                    16 lighttpd
                    16 sshlockout_pf
                    16 tcpdump
                    24 tcsh
                    25 dhcpd
                    33 sshd
                    36 minicron
                    41 syslogd
                    54 ntpd
                   249 openvpn
                  1535 php
                  1861 filterdns
                  
                  

                  But a 2.2 system that I just updated/rebooted looks like:

                  [2.2-BETA][root@apu22.localdomain]/root(1): fstat | awk '\!/CMD/{print $2}' | sort | uniq -c | sort -n
                     2 kernel
                     2 md0
                     2 md1
                     3 init
                     4 getty
                     7 awk
                     7 rrdtool
                     7 uniq
                     8 apinger
                     8 fstat
                     8 login
                     8 sshlockout_pf
                     9 tcsh
                    12 sleep
                    14 cron
                    14 dnsmasq
                    14 sort
                    15 filterlog
                    16 check_reload_status
                    17 devd
                    17 inetd
                    17 openvpn
                    21 dhcpd
                    22 lighttpd
                    22 ntpd
                    22 sshd
                    36 dhclient
                    36 minicron
                    39 php-fpm
                    42 syslogd
                    47 sh
                  
                  

                  So the "php" and "filterdns" on the 2.1.5 production system have something wrong - there is no way they should be sitting with so many open file handles.
                  A problem like this will cause intermittent system problems after some random days/weeks/months.

                  As the Greek philosopher Isosceles used to say, "There are 3 sides to every triangle."
                  If I helped you, then help someone else - buy someone a gift from the INF catalog http://secure.inf.org/gifts/usd/

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                  • P
                    petr
                    last edited by

                    Exactly my concern!

                    I think the problem exhibits itself when filterdns (and also layer7 daemon for me) get restarted - could be gateway alarm, refresh of rules, etc. They do not seem to release the old files and just allocate new file handles.

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                    • P
                      phil.davis
                      last edited by

                      I raised a bug report: https://redmine.pfsense.org/issues/3951
                      That way it does not get forgotten.

                      As the Greek philosopher Isosceles used to say, "There are 3 sides to every triangle."
                      If I helped you, then help someone else - buy someone a gift from the INF catalog http://secure.inf.org/gifts/usd/

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