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    DHCP no free leases

    DHCP and DNS
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    • R
      rovshango
      last edited by

      Hi,

      I got often this message:

      DHCPDISCOVER from c8:3d:97:4a:88:98 via 10.64.160.1 [More Information] : network 10.64.160.0 [More Information] /22: no free leases
      Is it OK/enough to free dhcp leases files?
      Thanks.

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      • DerelictD
        Derelict LAYER 8 Netgate
        last edited by

        What's the application?  How long are your lease timeouts?  How big is the pool?

        No, you should probably leave the leases file alone.

        Chattanooga, Tennessee, USA
        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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        • R
          rovshango
          last edited by

          Hi,

          Thanks for reply.
          Please see attachment.

          dhcp_rovshan.JPG
          dhcp_rovshan.JPG_thumb

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          • chpalmerC
            chpalmer
            last edited by

            Whats the application?

            Wifi cafe?  School?  Its hard to tell you if we don't know who or what your giving internet connectivity to.

            You might consider a /23 on your LAN and increase your DHCP pool by about 200 users and see if the problem continues.

            Triggering snowflakes one by one..
            Intel(R) Core(TM) i5-4590T CPU @ 2.00GHz on an M400 WG box.

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            • R
              rovshango
              last edited by

              We just provide free Wi-Fi in random places.
              Mostly people connect with their hand devices and can login by generated password (SMS sending).

              Before me other person cleared dhcp leases file and problem solved.

              We had /24 at the beginning, but now we need more. So I changed network range.

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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                And it sounds like you need more yet again.

                You need to balance the need to keep the lease history so people get the same IP versus the network size.

                Is there captive portal involved?

                If you don't really need those reserved 100 addresses I'd add those to the pool like now - or at least as many as you can.

                Chattanooga, Tennessee, USA
                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                • R
                  rovshango
                  last edited by

                  Yes CP is main part :)

                  10.64.160.0/22 (255.255.252.0) means there 1022 available address (10.64.160.0 - 10.64.163.255)
                  I can see in daily report that there are maximum 200 users.
                  And this error I got week ago and today.

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                  • DerelictD
                    Derelict LAYER 8 Netgate
                    last edited by

                    You have a max DHCP lease timeout of 3660 seconds (61 minutes).

                    Regardless of the maximum on the CP at one time, how many devices are connecting to your Wi-Fi and getting an address in your busiest hour?  Note that they don't have to punch through the portal to chew up a DHCP lease.

                    How do you want your CP to behave?

                    Chattanooga, Tennessee, USA
                    A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                    DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                    Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                    • R
                      rovshango
                      last edited by

                      I can say busies hour there will be 100-200 user same time.
                      Also in attachment you can find settings of CP.

                      As there 1022 (-100) available address, I want users to get IP addresses.

                      cp_rovshan.JPG
                      cp_rovshan.JPG_thumb

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                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        You are running out of leases, friend.  Something is chewing them up.

                        I say again, a user doesn't have to log in to the CP to consume a DHCP lease for an hour.  All they have to do is connect to the BSSID and get a lease.  Unfortunately, ISC dhcpd absolutely SUCKS when it comes to summarizing exactly what is going on with your lease pool.

                        Something like this: http://dhcpstatus.sourceforge.net/

                        might give you some additional insight as to exactly what is happening to your lease pool.

                        If you're not syslogging to a syslog server you probably want to do that too.  My dhcp log on pfSense rolls over about every 5 minutes.

                        900 leases with an hour expire seems like it ought to be enough.

                        Chattanooga, Tennessee, USA
                        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                        • R
                          rovshango
                          last edited by

                          Yeah, that part I understand, that user gets IP address first then CP starts to working,
                          I just want each IP address after 60 minutes to be freed :(

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                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            That's how you have it set.  That's how it should be working.

                            Note that those settings take effect when the lease is obtained so if you just changed it it will take some time to take effect.

                            Status > DHCP Leases shows you the current leases.  Do they not look right?

                            Chattanooga, Tennessee, USA
                            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                            Do Not Chat For Help! NO_WAN_EGRESS(TM)

                            1 Reply Last reply Reply Quote 0
                            • R
                              rovshango
                              last edited by

                              It shows 423 online&active and same time I am getting same alarm :(.

                              Well when before this topic I cleaned dhcpd.leases file but it got filled with old data again.

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                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by

                                What shows 423 online and active?  The DHCP leases?

                                You have to account for the offline leases that haven't expired yet.  As far as I know, Status > DHCP Leases shows a lease as offline if there is no corresponding ARP entry, meaning the IP has dropped off the network.

                                Obviously you need a bigger lease pool.

                                Chattanooga, Tennessee, USA
                                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                                • R
                                  rovshango
                                  last edited by

                                  Thanks for info.
                                  So I will change network range then.
                                  Let's see what will happen.

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                                  • R
                                    rovshango
                                    last edited by

                                    Hi all,

                                    Very strange - CP shows me only 40 active users.
                                    But I am getting same syslog again.

                                    Despite there are almost 1000 free IP addresses.

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                                    • DerelictD
                                      Derelict LAYER 8 Netgate
                                      last edited by

                                      How do you know what addresses are free?

                                      Chattanooga, Tennessee, USA
                                      A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                      DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                      Do Not Chat For Help! NO_WAN_EGRESS(TM)

                                      1 Reply Last reply Reply Quote 0
                                      • R
                                        rovshango
                                        last edited by

                                        You mean, even though if CP will disconnect them, they will use IP address till lease time?

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                                        • DerelictD
                                          Derelict LAYER 8 Netgate
                                          last edited by

                                          Of course.  CP has nothing to do with DHCP.  They have to play together nicely and be set up in a complementary fashion but one doesn't influence the other.  Look into those dhcp status scripts I posted earlier.

                                          Chattanooga, Tennessee, USA
                                          A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                                          DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                                          Do Not Chat For Help! NO_WAN_EGRESS(TM)

                                          1 Reply Last reply Reply Quote 0
                                          • R
                                            rovshango
                                            last edited by

                                            Well my CP set for 59 minutes, so I should set DHCP lease time also 59 minutes.
                                            Then I think lease/pool will be freed correctly.

                                            Yes I saw your post, I had difficulties installed in into pfSense, as there some library dependencies. I will try again :)

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