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    Dhclient wants to renew resolv.conf every 60 seconds for WAN

    Scheduled Pinned Locked Moved DHCP and DNS
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    • F Offline
      flgk
      last edited by

      I don't know if they will give me correct answers, they have a poor technical support

      Is it the normal behaviour of dhclient to renew resolv.conf at the end of the lease time?

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      • D Offline
        doktornotor Banned
        last edited by

        Hmmm yeah, poor support and idiotic settings. Kindly post the output of this:

        
        tail -n 20 /var/db/dhclient.leases.* | grep dhcp-lease-time
        
        
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        • F Offline
          flgk
          last edited by

          The output is :

          $ tail -n 20 /var/db/dhclient.leases.* | grep dhcp-lease-time
            option dhcp-lease-time 600;
          

          I tried also a cat /var/db/dhclient.lases.*

          The output is the following :

          lease {
            interface "re0";
            fixed-address 82.250.119.XXX;
            next-server 82.250.119.254;
            option subnet-mask 255.255.255.0;
            option routers 82.250.119.254;
            option domain-name-servers 212.27.40.241,212.27.40.240;
            option broadcast-address 82.250.119.255;
            option dhcp-lease-time 600;
            option dhcp-message-type 5;
            option dhcp-server-identifier 82.250.119.254;
            option dhcp-renewal-time 60;
            option dhcp-rebinding-time 300;
            renew 0 2015/8/30 12:55:57;
            rebind 0 2015/8/30 12:59:57;
            expire 0 2015/8/30 13:04:57;
          }

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          • johnpozJ Online
            johnpoz LAYER 8 Global Moderator
            last edited by

            yeah my lease is 7200 seconds or 2 hours.. So about every hour it would renew.

            Well that was an older lease.. Might be better to post the whole lease file for your wan nic

            So for example the end of the file was old lease

            My current lease is

            lease {
              interface "em0";
              fixed-address 24.13.xx.xx;
              option subnet-mask 255.255.248.0;
              option routers 24.13.176.1;
              option domain-name-servers 75.75.75.75,75.75.76.76;
              option host-name "pfSense";
              option domain-name "hsd1.il.comcast.net.";
              option broadcast-address 255.255.255.255;
              option dhcp-lease-time 345600;
              option dhcp-message-type 5;
              option dhcp-server-identifier 69.252.202.7;
              renew 0 2015/8/30 15:07:27;
              rebind 2 2015/9/1 03:07:27;
              expire 2 2015/9/1 15:07:27;
            }

            Which you can see has a long LEASE!!!

            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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            • F Offline
              flgk
              last edited by

              In my last edit of my previous post, I put the last lease but the file is full of leases and the date you can read at the end of each lease are diffrent of 1 minutes for all of them :

              lease {
                interface "re0";
                fixed-address 82.250.119.XXX;
                next-server 82.250.119.254;
                option subnet-mask 255.255.255.0;
                option routers 82.250.119.254;
                option domain-name-servers 212.27.40.241,212.27.40.240;
                option broadcast-address 82.250.119.255;
                option dhcp-lease-time 600;
                option dhcp-message-type 5;
                option dhcp-server-identifier 82.250.119.254;
                option dhcp-renewal-time 60;
                option dhcp-rebinding-time 300;
                renew 0 2015/8/30 12:53:57;
                rebind 0 2015/8/30 12:57:57;
                expire 0 2015/8/30 13:02:57;
              }
              lease {
                interface "re0";
                fixed-address 82.250.119.XXX;
                next-server 82.250.119.254;
                option subnet-mask 255.255.255.0;
                option routers 82.250.119.254;
                option domain-name-servers 212.27.40.241,212.27.40.240;
                option broadcast-address 82.250.119.255;
                option dhcp-lease-time 600;
                option dhcp-message-type 5;
                option dhcp-server-identifier 82.250.119.254;
                option dhcp-renewal-time 60;
                option dhcp-rebinding-time 300;
                renew 0 2015/8/30 12:54:57;
                rebind 0 2015/8/30 12:58:57;
                expire 0 2015/8/30 13:03:57;
              }
              lease {
                interface "re0";
                fixed-address 82.250.119.XXX;
                next-server 82.250.119.254;
                option subnet-mask 255.255.255.0;
                option routers 82.250.119.254;
                option domain-name-servers 212.27.40.241,212.27.40.240;
                option broadcast-address 82.250.119.255;
                option dhcp-lease-time 600;
                option dhcp-message-type 5;
                option dhcp-server-identifier 82.250.119.254;
                option dhcp-renewal-time 60;
                option dhcp-rebinding-time 300;
                renew 0 2015/8/30 12:55:57;
                rebind 0 2015/8/30 12:59:57;
                expire 0 2015/8/30 13:04:57;
              }

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              • johnpozJ Online
                johnpoz LAYER 8 Global Moderator
                last edited by

                yeah all of those are really short LEASES!!!

                See this
                option dhcp-renewal-time 60;

                That is what is causing your problem…  And your lease is only 600 seconds or 10 minutes anyway..

                Seems like your isp is NUTS!!!  Why they should need someone to renew or only have leases for those amounts of times is crazy.. Is this some sort of cell connection or wireless connection?

                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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                • F Offline
                  flgk
                  last edited by

                  How can I change this ? Is it function or config file to override my ISP's dhcp leases ?

                  Seems like your isp is NUTS!!!  Why they should need someone to renew or only have leases for those amounts of times is crazy.. Is this some sort of cell connection or wireless connection?

                  No I use my ADSL line (my ISP is "Free") not a game word  :P

                  I'm agree, totally nuts

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                  • johnpozJ Online
                    johnpoz LAYER 8 Global Moderator
                    last edited by

                    They have added some advanced stuff to dhcp client options.. And you can request stuff, etc.. But I have not had time to play with it..  I would not suggest over riding what they give you for a lease locally because they would just drop the lease on their end if not renewed..  And then someone else could get your same IP and that would cause problems

                    You can try requesting specific setting.. But if they do not comply you prob best to call them..

                    This is a FREE isp??  Anyone can use it?  If so that might explain really really short leases – they have limited IP space and want to make sure if your not on you loose your IP..

                    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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                    • F Offline
                      flgk
                      last edited by

                      Free is the name of my ISP, they have plenty IPs but they gives static IPs only for their subscribers located in areas where the telephone exchange is "dégroupé" means they have their own DSLAMs and I'm located where the telephone exchange is held by the historical ISP, so Free have decided to assign dynamic IP for customers which are not connected to their devices…

                      Their modem (at home) distribute the public IP for the first network card which ask it, so anything I connect on their modem will receive the same public IP (and there'll be a conflict) it's not a PPP connection on pfsense.
                      Of course I've disabled routing on their modem.

                      I have the possibility to ask them a static IP, but I would prefer try to solve this issue using software. The other solution is to use a NAT behind pfsense but it's not very clean.

                      Do you have any idea to "hack" the dhcp leases ? Why do I get so much leases on /var/db/dhclient.leases.* ?

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                      • D Offline
                        doktornotor Banned
                        last edited by

                        Your ISP are positively a bunch of clueless idiots. There are advanced settings for DHCP client, but I very much doubt they'll be honored. (By default, 7200 secs lease is requested when those advanced settings are untouched. You are getting 10 minutes and even 1 minute renewal time!!! Totally crazy!!! ISP => full retard!!!

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                        • F Offline
                          flgk
                          last edited by

                          @doktornotor:

                          Your ISP are positively a bunch of clueless idiots. There are advanced settings for DHCP client, but I very much doubt they'll be honored. (By default, 7200 secs lease is requested when those advanced settings are untouched. You are getting 10 minutes and even 1 minute renewal time!!! Totally crazy!!! ISP => full retard!!!

                          Indeed ;D

                          What about the field "Option modifiers" in advanced settings of WAN ? is there a way to override anyway the renewal ?

                          The perfect configuration would a large lease, and when the gateway is down within the lease, let dhclient trying to renew its lease. The IP address changes is on 24 hours after the modem has got the ADSL link, again a crazy rule

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                          • D Offline
                            doktornotor Banned
                            last edited by

                            I think these are just useless for you. With this kind of settings, they'll hand out your "24hours" IP to anyone as soon as you fail to renew the lease on those preset idiotic intervals. Request a static IP or switch ISPs, I'd say.

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                            • johnpozJ Online
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              Again you can not just go changing your end of what the dhcp server gave you.. If it gave you a lease of X and you tell your client no use Y that is longer than X your most likely going to run into problems.

                              As to why you might see more than one entry in leases.. Could be other dhcp servers..  Could be that you did a reboot or something of pfsense and just got a new lease vs renew of old one..  Lots of reasons..  I don't think there is any code to clean up that leases file ever?  Guess you could do it manually if bothered you?

                              So I deleted everything in the file and then released and renewed my wan and now just show one lease

                              [2.2.4-RELEASE][root@pfSense.local.lan]/root: cat /var/db/dhclient.leases.em0
                              lease {
                                interface "em0";
                                fixed-address 24.13.x.x;
                                option subnet-mask 255.255.248.0;
                                option routers 24.13.x.x;
                                option domain-name-servers 75.75.75.75,75.75.76.76;
                                option host-name "pfSense";
                                option domain-name "hsd1.il.comcast.net.";
                                option broadcast-address 255.255.255.255;
                                option dhcp-lease-time 176803;
                                option dhcp-message-type 5;
                                option dhcp-server-identifier 69.252.202.7;
                                renew 1 2015/8/31 14:34:06;
                                rebind 2 2015/9/1 08:59:06;
                                expire 2 2015/9/1 15:07:28;
                              }
                              [2.2.4-RELEASE][root@pfSense.local.lan]/root:

                              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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                              • D Offline
                                doktornotor Banned
                                last edited by

                                The history on those lease files is kept by design.

                                dhclient.conf(5)

                                
                                     The DHCP client may decide after some period of time (see PROTOCOL
                                     TIMING) that it is	not going to succeed in contacting a server.  At that
                                     time, it consults its own database	of old leases and tests each one that
                                     has not yet timed out by pinging the listed router	for that lease to see
                                     if	that lease could work.
                                
                                
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                                • F Offline
                                  flgk
                                  last edited by

                                  Done, now I have a static IP (it's been a while that I had to do it) I will disable DHCP on WAN, but the problem of short leases is still ongoing with pfsense.

                                  @johnpoz No, every entry are (was) for the WAN.

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                                  • D Offline
                                    doktornotor Banned
                                    last edited by

                                    What short leases? Shouldn't have your WAN set up as DHCP at all when your IP is static. You need to get rid of DHCP altogether with this ISP.

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                                    • johnpozJ Online
                                      johnpoz LAYER 8 Global Moderator
                                      last edited by

                                      Yeah if you setup wan as static there wouldn't be any dhcp client doing anything for that interface.

                                      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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