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    Strange address Shown in the dhcp leases

    Scheduled Pinned Locked Moved General pfSense Questions
    57 Posts 12 Posters 14.1k Views
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    • D Offline
      divsys
      last edited by

      i did ssh to the Machine (Reminds me person of interest)
      and Paste this /var/dhcpd/var/db: cat dhcpd.leases

      try:
      cd /var/dhcpd/var/db
      cat dhcpd.leases

      or:
      cat /var/dhcpd/var/db/dhcpd.leases

      or:

      less /var/dhcpd/var/db/dhcpd.leases

      These are basic FreeBSD commands.
      There are many primers/HowTos on the commands and how/when to use them available with a quick Google search.

      -jfp

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      • F Offline
        firefox
        last edited by

        this is what i got

        # The format of this file is documented in the dhcpd.leases(5) manual page.
        # This lease file was written by isc-dhcp-4.2.6
        
        lease 192.168.0.30 {
          starts 1 2015/05/25 04:04:19;
          ends 1 2015/05/25 06:04:19;
          tstp 1 2015/05/25 06:04:19;
          cltt 1 2015/05/25 04:04:19;
          binding state free;
          hardware ethernet 00:1c:85:0d:1d:68;
          uid "\001\000\034\205\015\035h";
        }
        lease 192.168.0.31 {
          starts 3 2015/05/27 12:43:26;
          ends 3 2015/05/27 14:43:26;
          tstp 3 2015/05/27 14:43:26;
          cltt 3 2015/05/27 12:43:26;
          binding state free;
          hardware ethernet 54:35:30:b1:da:f5;
          uid "\001T50\261\332\365";
        }
        lease 192.168.0.32 {
          starts 0 2015/05/31 19:16:46;
          ends 0 2015/05/31 21:16:46;
          tstp 0 2015/05/31 21:16:46;
          cltt 0 2015/05/31 19:16:46;
          binding state free;
          hardware ethernet 94:35:0a:23:07:f3;
          uid "\001\2245\012#\007\363";
        }
        lease 192.168.0.33 {
          starts 4 2015/06/04 06:42:41;
          ends 5 2015/06/05 06:42:41;
          tstp 5 2015/06/05 06:42:41;
          cltt 4 2015/06/04 06:42:41;
          binding state free;
          hardware ethernet 0c:74:c2:e1:78:f9;
          uid "\001\014t\302\341x\371";
        }
        lease 192.168.0.36 {
          starts 4 2015/06/11 15:39:16;
          ends 4 2015/06/11 17:39:16;
          tstp 4 2015/06/11 17:39:16;
          cltt 4 2015/06/11 15:39:16;
          binding state free;
          hardware ethernet f8:d1:11:16:4b:d9;
        }
        lease 192.168.0.35 {
          starts 4 2015/06/11 15:41:11;
          ends 4 2015/06/11 17:41:11;
          tstp 4 2015/06/11 17:41:11;
          cltt 4 2015/06/11 15:41:11;
          binding state free;
          hardware ethernet 00:1b:38:46:27:6b;
        }
        lease 192.168.0.37 {
          starts 4 2015/06/11 15:41:19;
          ends 4 2015/06/11 17:41:19;
          tstp 4 2015/06/11 17:41:19;
          cltt 4 2015/06/11 15:41:19;
          binding state free;
          hardware ethernet 00:1c:bf:11:dc:62;
        }
        lease 192.168.0.42 {
          starts 5 2015/06/12 08:38:46;
          ends 5 2015/06/12 10:38:46;
          tstp 5 2015/06/12 10:38:46;
          cltt 5 2015/06/12 08:38:46;
          binding state free;
          hardware ethernet 94:35:0a:23:07:f3;
          uid "\001\2245\012#\007\363";
        }
        server-duid "\000\001\000\001\034c\215 \000\002\263\013\253.";
        
        
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        • H Offline
          hda
          last edited by

          @firefox:

          Could it be that someone is trying to get in to the network. Wirelessly ??

          If you are suspicious about (wireless) connections, then do ACL, explicitly allow MAC addresses (therefore deny the undefined) in your AP.

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          • F Offline
            firefox
            last edited by

            what is ACL ?

            1 Reply Last reply Reply Quote 0
            • H Offline
              hda
              last edited by

              Access Control List(s)

              In pfSense have look at Services: DHCP server [MAC Address Control]

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              • F Offline
                firefox
                last edited by

                @johnpoz:

                Why don't you look in the actual file for what it shows for the end date, and see what we have..

                example
                [2.2.2-RELEASE][root@pfSense.local.lan]/var/dhcpd/var/db: cat dhcpd.leases

                lease 192.168.2.216 {
                  starts 6 2015/06/13 12:04:00;
                  ends 3 2015/06/17 12:04:00;
                  cltt 6 2015/06/13 12:04:00;
                  binding state active;
                  next binding state free;
                  rewind binding state free;
                  hardware ethernet ac:fd:ec:62:34:97;
                  uid "\001\254\375\354b4\227";
                  client-hostname "Johns-Phone";

                cltt stands for Client Last Transaction Time, not sure why its showing that vs the end date?  I would also track down what device it is, that is clearly an ODD mac..

                Where the last line ```
                client-hostname "Johns-Phone";

                
                It is not registered anything in the output of the command (in my computer)
                
                and now it is cltt 6
                
                

                lease 192.168.0.43 {
                  starts 6 2015/06/13 21:31:09;
                  ends never;
                  cltt 6 2015/06/13 21:31:09;
                  binding state active;
                  next binding state free;
                  rewind binding state free;
                  hardware ethernet 00🆎00:00:00:00;

                
                How exactly do I use with this ACL option
                
                I have to enroll all Mac addresses of all computers on the network
                One by one comma separated
                
                it says partial MAC addresses
                Which part ?
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                • M Offline
                  motionthings
                  last edited by

                  edit3
                  My post was about wireless security, and did not belong here.
                  I'll not be offended if it gets deleted. http://pastebin.com/QaGHXbU4
                  /edit 3

                  edit2
                  Looks like @cmb has a really good answer. Thanks :-)
                  /edit2

                  Intel Core i3, 8GB RAM, 2x Intel Gigabit NIC's.
                  CURRENT network: https://cacoo.com/diagrams/1Fh6EcMdZLjGq3zj
                  Planned network: https://cacoo.com/diagrams/y2rMw37kzlzcHzZy
                  Read BOFH (Bastard Operator From Hell): http://bofh.ntk.net/BOFH/index.php

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                  • H Offline
                    hda
                    last edited by

                    @firefox:

                    …
                    it says partial MAC addresses
                    Which part ?

                    http://www.gcstech.net/macvendor/index.php?node=macsea

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                    • C Offline
                      cmb
                      last edited by

                      That's a BOOTP lease, which is why it looks weird.

                      Hostnames are only there where the client sends one. It not having one isn't unusual, especially for the types of devices that do BOOTP.

                      There are very limited devices that use BOOTP. Generally they're very old (1990s era printers for instance), or atypical embedded devices. It could be some broken device as well.

                      It seems to be a semi-active device, or at least your time of last contact (cltt) seems to update. If you have a managed switch, try tracking down that MAC address' port and see what's plugged into it. If you don't have a managed switch it'll be harder to track down, though not too difficult if you have a small network. Unplug most things, see if it's still updating. Add things back one by one. See when that comes back. Or just try reaching the device to see what it's running. A nmap scan with OS identification enabled might be telling.

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                      • C Offline
                        cmb
                        last edited by

                        @Jailer:

                        checking now but even if it is why would it be set to never expire?

                        BOOTP leases never expire.

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                        • C Offline
                          cmb
                          last edited by

                          That MAC seems to be something a number of other people have seen pulling BOOTP leases, though at a glance through Google results I don't see anyone who found the source of it. Might be worthwhile to dig through those results more closely.
                          https://www.google.com/webhp?q=%2200🆎00:00:00:00%22

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                          • F Offline
                            firefox
                            last edited by

                            I know
                            Already encountered this once
                            Last time i  simply blocked the address

                            This time I wanted to know where it came from

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                            • johnpozJ Offline
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              well track it down – its clearly on your network..

                              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 25.07 | Lab VMs 2.8, 25.07

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                              • F Offline
                                firefox
                                last edited by

                                I've checked
                                No device in my network
                                Have such address

                                That's why I ask

                                I blocked it again
                                As before

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                                • JailerJ Offline
                                  Jailer
                                  last edited by

                                  Yeah it's definitely not a device on my network, this is my home network and every device is accounted for.

                                  Could it possibly be my Dlink router that I'm using as an AP? DHCP is turned off on the router but the wireless does occasionally quit working, especially when it gets warmer out, requiring a power cycle to restore it.

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                                  • johnpozJ Offline
                                    johnpoz LAYER 8 Global Moderator
                                    last edited by

                                    Sorry but its has to be something on your network..

                                    Could be something like a media player, dvr, doubt its your dlink.. But sure..  When you delete the lease how long until it comes back?  Is it every 24 hours, every 1 hour, every 10 minutes?  Does it ping to that IP you gave it?

                                    What interface are you seeing it on?  Lan, Wan, Wireless?  You don't have a smart switch that shows you mac address table?

                                    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 25.07 | Lab VMs 2.8, 25.07

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                                    • JailerJ Offline
                                      Jailer
                                      last edited by

                                      Shows up on LAN, no smart switch. I'll have to check when I get home to see if it's back again. Had a power outage yesterday and as of last night it wasn't there.

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                                      • johnpozJ Offline
                                        johnpoz LAYER 8 Global Moderator
                                        last edited by

                                        Is your lan bridged to your wireless?  If showing up on your lan - clearly its on your network ;)

                                        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 25.07 | Lab VMs 2.8, 25.07

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                                        • JailerJ Offline
                                          Jailer
                                          last edited by

                                          No bridge, just DHCP disabled and static IP so it's working as an AP. pfsense is handling all the routing.

                                          Checked my leases and it's not there any more. I dunno, maybe something left over from one of the many VM's I've had running? I'm out of ideas.

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                                          • johnpozJ Offline
                                            johnpoz LAYER 8 Global Moderator
                                            last edited by

                                            So your wireless is on the same network as your lan - ie bridged..

                                            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 25.07 | Lab VMs 2.8, 25.07

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