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    Strange address Shown in the dhcp leases

    Scheduled Pinned Locked Moved General pfSense Questions
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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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                                • JailerJ Offline
                                  Jailer
                                  last edited by

                                  If that's what "bridged" means then yes. It is on the same subnet as LAN.

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                                  • F Offline
                                    firefox
                                    last edited by

                                    @johnpoz:

                                    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?

                                    Here is a list of all the addresses on my network
                                    1-27 are static addresses

                                    and 43 is Dynamic address

                                    If I shut down the DHCP
                                    I assume he could not get access to the network
                                    but Guests also can not

                                    If I delete this address
                                    After a while, it comes back
                                    Can be after 10 minutes
                                    Can be after two hours
                                    Can be after 16 hours
                                    No fixed time

                                    You can not ping to it

                                    PING 192.168.0.43 (192.168.0.43) 56(84) bytes of data.
                                    From 192.168.0.2 icmp_seq=1 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=2 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=3 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=4 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=5 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=6 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=7 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=8 Destination Host Unreachable
                                    From 192.168.0.2 icmp_seq=9 Destination Host Unreachable
                                    
                                    

                                    I do not have a smart switch
                                    i see this address on my LAN
                                    i have WAN ,LAN, WIFI, and BRIDGE (lan and wifi)

                                    I have 2 routers that serve as an access point
                                    edimax 192.168.0.104
                                    dlink 192.168.0.101
                                    a network card on the pfsense also as AP (the wifi)
                                    and one cisco access point (192.168.0.25)
                                    all have fixed (static) IP
                                    DHCP shut down in the routers

                                    I went physically at home  to each device that connects to the network
                                    And checked Mack addresses the same as in the DHCP leases

                                    ![mac address.png](/public/imported_attachments/1/mac address.png)
                                    ![mac address.png_thumb](/public/imported_attachments/1/mac address.png_thumb)

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                                    • T Offline
                                      tim.mcmanus
                                      last edited by

                                      If you have a *NIX box on your network you can run nmap to do some network discovery and determine what is where.  I think there's also an nmap package for pfSense that would also scan your network and determine what is running where.  Very handy and powerful utility.

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                                      • F Offline
                                        firefox
                                        last edited by

                                        what is "NIX box" ??

                                        Know the package which is installed
                                        It does not show anything

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                                        • johnpozJ Offline
                                          johnpoz LAYER 8 Global Moderator
                                          last edited by

                                          Well without 3 different AP and wireless and wired on the same lan without a smart switch.. Yeah going to have a hard time tracking it down.

                                          So your sure its showing up on your lan interface?  Or your just seeing it hit your dhcp server?  Why don't you sniff for the bootp packets..  This might give you some better clue to what the device in the details of the packet.

                                          And you don't need a nix (unix/linux) box to run nmap, runs on windows just fine.  Not sure that would help - the OS identification isn't very good if you ask me.

                                          So can not ping, but it arps??  So when you try and ping that IP, and you look in your arp table you see it?

                                          Destination host unreach normally means it didn't arp..

                                          So no real AP, or smart switch - tracking down something like this can be tricky.. If you had a smart switch and real AP you could see where the mac is listed on physical port and what macs are trying to associate to your AP..

                                          So is your wireless open, or secured..  Change your psk, if can not assoicate with your wireless its not possible for it to get a lease from your dhcp server.  If still happens could be one of your routers acting as AP..  Turn 1 off at a time until you don't get it showing up any more.

                                          Do you run any sort of visualization.. How did you check for the mac exactly on all your devices?

                                          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

                                            So your sure its showing up on your lan interface?  Or your just seeing it hit your dhcp server?

                                            i see it on the DHCP leases not in the dhcp server

                                            Why don't you sniff for the bootp packets..  This might give you some better clue to what the device in the details of the packet.

                                            how do i do that ?

                                            So can not ping, but it arps??  So when you try and ping that IP, and you look in your arp table you see it?

                                            no cant see it in the arp

                                            there are all the options

                                            Running: /usr/local/bin/nmap  -sP -PR '192.168.0.43'
                                            Starting Nmap 6.40 ( http://nmap.org ) at 2015-06-16 17:03 IDT
                                            Note: Host seems down. If it is really up, but blocking our ping probes, try -Pn
                                            Nmap done: 1 IP address (0 hosts up) scanned in 0.52 seconds
                                            
                                            Running: /usr/local/bin/nmap  -sS -P0 -sV -O '192.168.0.43'
                                            Starting Nmap 6.40 ( http://nmap.org ) at 2015-06-16 17:04 IDT
                                            Nmap done: 1 IP address (0 hosts up) scanned in 2.95 seconds
                                            
                                            Running: /usr/local/bin/nmap  -sT '192.168.0.43'
                                            Starting Nmap 6.40 ( http://nmap.org ) at 2015-06-16 17:05 IDT
                                            Note: Host seems down. If it is really up, but blocking our ping probes, try -Pn
                                            Nmap done: 1 IP address (0 hosts up) scanned in 0.49 seconds
                                            
                                            Running: /usr/local/bin/nmap  -sS -P0 -sV -O '192.168.0.43'
                                            Starting Nmap 6.40 ( http://nmap.org ) at 2015-06-16 17:06 IDT
                                            Nmap done: 1 IP address (0 hosts up) scanned in 2.07 seconds
                                            
                                            

                                            So no real AP, or smart switch - tracking down something like this can be tricky.. If you had a smart switch and real AP you could see where the mac is listed on physical port and what macs are trying to associate to your AP..

                                            the cisco is real access point

                                            So is your wireless open, or secured

                                            my wireless is secured

                                            If still happens could be one of your routers acting as AP..

                                            my routers  are acting as AP as i said

                                            Do you run any sort of visualization.. How did you check for the mac exactly on all your devices?

                                            i went to every computer and tv and printer and lap top
                                            and check (i go to setting Depending on the device And saw the mac address)

                                            ![home.plex - Status DHCP leases - 2015-06-16_17.10.12.png](/public/imported_attachments/1/home.plex - Status DHCP leases - 2015-06-16_17.10.12.png)
                                            ![home.plex - Status DHCP leases - 2015-06-16_17.10.12.png_thumb](/public/imported_attachments/1/home.plex - Status DHCP leases - 2015-06-16_17.10.12.png_thumb)
                                            ![home.plex - Diagnostics ARP Table - 2015-06-16_17.16.50.png](/public/imported_attachments/1/home.plex - Diagnostics ARP Table - 2015-06-16_17.16.50.png)
                                            ![home.plex - Diagnostics ARP Table - 2015-06-16_17.16.50.png_thumb](/public/imported_attachments/1/home.plex - Diagnostics ARP Table - 2015-06-16_17.16.50.png_thumb)
                                            ![Cisco IOS Series AP - 2015-06-16_17.18.38.png](/public/imported_attachments/1/Cisco IOS Series AP - 2015-06-16_17.18.38.png)
                                            ![Cisco IOS Series AP - 2015-06-16_17.18.38.png_thumb](/public/imported_attachments/1/Cisco IOS Series AP - 2015-06-16_17.18.38.png_thumb)

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