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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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    • H
      heper
      last edited by

      same here on an old p4 that got updated from 2.0.x to 2.1 alpha->beta->release
      every 2 weeks i need to restart the service.

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      • S
        Smakodak
        last edited by

        I'm joining in. Since upgrading to 2.1 Release, I have this problem too.

        resolver log: dnsmasq[61060]: failed to load names from /etc/hosts: Too many open files in system
        system log: kernel: kern.maxfiles limit exceeded by uid 65534, please see tuning(7).

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        • H
          heper
          last edited by

          in my case it appears to have been caused by a harddrive that was starting to fail … it died completely on monday ;)

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          • G
            gabrielpc1190
            last edited by

            Im on 2.1-Release and had to reboot my system today because I lost dns resolving and that log was thousands of times.
            I tried the fstab and had similar to this:

            […]
            root    filterdns  28615 5663 /        14743744 -rw-r–r--    613  r
            root    filterdns  28615 5664 /        14743744 -rw-r--r--    613  r
            root    filterdns  28615 5665 /        14743744 -rw-r--r--    613  r
            root    filterdns  28615 5666 /        14743744 -rw-r--r--    613  r
            root    filterdns  28615 5667 /        14743744 -rw-r--r--    613  r
            root    filterdns  28615 5668 /        14743744 -rw-r--r--    613  r
            root    filterdns  28615 5669 /        14743744 -rw-r--r--    613  r

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            • M
              mircsicz
              last edited by

              +1 for me…

              EDIT:
              I solved the prob by writing the 2.1.2 *.img to another CF & restoring the config...

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              • S
                silvertip257
                last edited by

                I've seen this "max files" problem every couple of months probably since January-ish of this year.
                Past related posts (0) (1) indicate there is a problem, but don't offer a solution and are quite dated.

                I have a PC Engines ALIX 2D13 that I've had for few years now.
                The pfSense Store sells these (2) so I'd figure these would be well supported.

                Today dnsmasq was no longer processing DHCP requests.  I could have statically assigned an IP address and tried to access the unit, but instead consoled into the device.  I ended up consoling into the unit and found system.log indicating the board was low on memory.  This unit had only been running for approximately 47 days since my upgrade to version 2.1.2.  I ended up rebooting it and also opted to upgrade to version 2.1.3 afterwards.

                In the past when dnsmasq wouldn't process DNS queries, I found filterdns had quite a few files open (output from fstat).  I don't have a total count of open files from the time periods when there were problems.

                I whipped up the following one-liner for the future.  Maybe it's useful to somebody else as well.

                
                # filterdns open files
                fstat | awk '/filterdns/{i++} END{printf("%d files open by filterdns\n", i)}'
                
                # all open files per process plus a total
                fstat | awk '\!/CMD/{print $2} END{printf("* Total files open: %d", NR)}' | sort | uniq -c | sort -n
                
                

                I have a few aliases for my pf rules which have host names and one persistent IPSec tunnel.

                The unit has been up for <60 minutes now and has 20 open files by the filterdns user, but other users have many more open files.

                If pfSense developers (or anyone else) have any proactive tips as to what else I might look for or try, please reply!  Thanks.

                (0) https://forum.pfsense.org/index.php?topic=29885.0
                (1) https://forums.freebsd.org/viewtopic.php?&t=1553
                (2) http://store.pfsense.org/vk-2d13-black/

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                • C
                  Cristacul
                  last edited by

                  Hello

                  I had the same problem a couple of months ago. In my case pfBlocker was the cause (had a rule with whole world blocked except Europe) and eventually it crashed with a lot of filterdns files opened.

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                  • S
                    silvertip257
                    last edited by

                    Thanks for the reply Cristacul.

                    pfBlocker is not the cause for my problem since I'm not using it.

                    It is my understanding that firewall rules with (or other features that utilize) domain names are the only ones that utilize filterdns.
                    Might there be something else at work here causing my problem?

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                    • G
                      gabrielpc1190
                      last edited by

                      Same problem and not having pfBlocker.
                      I have pfSense 2.1.4 64bits  :(

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                      • S
                        silvertip257
                        last edited by

                        @silvertip257:

                        I whipped up the following one-liner for the future.  Maybe it's useful to somebody else as well.

                        
                        # filterdns open files
                        fstat | awk '/filterdns/{i++} END{printf("%d files open by filterdns\n", i)}'
                        
                        # all open files per process plus a total
                        fstat | awk '\!/CMD/{print $2} END{printf("* Total files open: %d", NR)}' | sort | uniq -c | sort -n
                        
                        

                        Here's an extension to my previous one-liner commands.
                        This one is more helpful to get the big picture (beyond what filterdns is doing).

                        
                        # spit out open files with a count per command and order them
                        
                        fstat | awk '\!/CMD/{print $2}' | sort | uniq -c | sort -n
                        
                        
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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/

                                          1 Reply Last reply Reply Quote 0
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