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    Solved: Unknown servers on VLAN

    Scheduled Pinned Locked Moved General pfSense Questions
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    • L
      lewis @johnpoz
      last edited by

      @johnpoz LOL, sometimes we get into trouble just for being curious I guess. But on the other hand, if no one ever questioned anything, things would come apart. Where is the balance? In your pay level maybe? :)

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      • L
        lewis
        last edited by

        DC tells me it's their own hardware and as someone mentioned, because I was scanning all interfaces.

        Thank you for the responses. Always learning :).

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator @lewis
          last edited by

          @lewis said in Unknown servers on VLAN:

          because I was scanning all interfaces.

          From the command you showed it wouldn't be scanning all interfaces, other then the interfaces you had that were in the networks you scanned. And then it would just send networks that were not directly attached out your default gateway. Which would be routed through your DCs network via your default gateway.

          An intelligent man is sometimes forced to be drunk to spend time with his fools
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          • L
            lewis
            last edited by

            There are three NICs connected in the pfsense box.
            One is WAN and two are LANs. All are of course routed internally so I'm sure LAN/WAN meet here and there.

            When I ran the nmap, I didn't specify an interface but I did specify a network.

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator @lewis
              last edited by johnpoz

              @lewis said in Unknown servers on VLAN:

              When I ran the nmap, I didn't specify an interface but I did specify a network.

              Exactly - so if you scanned 192.168/16 and you had say 2 lan networks of say 192.168.100/24 and 192.168.200/24

              It would scan those 2 networks because they are directly attached sending the traffic out those interface. But when it say scanned 192.168.101/24 out of your 16 it would of sent that to the default gateway out the wan.

              As to lan/wan meeting??

              If you scanned 10/8 and you had no interfaces in a 10.x network and or no other routes to get to 10.x then all of that traffic would of been sent to the default gateway.

              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 2.7.2, 24.11

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              • L
                lewis @johnpoz
                last edited by

                @johnpoz said in Unknown servers on VLAN:

                If you scanned 10/8 and you had no interfaces in a 10.x network and or no other routes to get to 10.x then all of that traffic would of been sent to the default gateway.

                Yes, there were no replies from anything in the 10 network.
                What I mean by LAN/WAN meeting is probably wrong. I was told by the DC that the LAN and WAN are fully separated networks within the infrastructure.

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator @lewis
                  last edited by

                  @lewis said in Unknown servers on VLAN:

                  DC that the LAN and WAN are fully separated networks within the infrastructure

                  Wells your "lans" are completely isolated because they are behind pfsense ;) into your own switches that do not connect to anything else other than your devices - right?

                  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 2.7.2, 24.11

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                  • L
                    lewis @johnpoz
                    last edited by

                    @johnpoz said in Unknown servers on VLAN:

                    Wells your "lans" are completely isolated because they are behind pfsense ;) into your own switches that do not connect to anything else other than your devices - right?

                    Not exactly since I have two LAN connections and one WAN connection. The WAN is just that but one LAN goes into my own switch and the other LAN goes to the DC's internal LAN network where I am given a private VLAN that acts as my own LAN in the DC.

                    Hope that makes sense :)

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator @lewis
                      last edited by johnpoz

                      @lewis said in Unknown servers on VLAN:

                      LAN goes to the DC's internal LAN network where I am given a private VLAN that acts as my own LAN in the DC.

                      Ah well then it could be possible for stuff to be on this network that you might not want on what is "your" network... So as suggested would check this network for devices that are not yours. You could do a arp scan, this is way better then doing a nmap scan.. Since you could scan for really any network at all that are on the same L2 (vlan)..

                      https://www.freebsd.org/cgi/man.cgi?query=arp-scan&sektion=&manpath=freebsd-release-ports

                      -arpspa=<s> or -s <s>
                      Use <s> as the source IP address. The address should be specified in dotted quad format; or the string "dest", which sets the source address to be the same as the target host address. This sets the 32-bit ar$spa field in the ARP packet. Some operating systems check this, and will only respond if the source address is within the network of the receiving interface. Others don't care, and will respond to any source address. By default, the outgoing interface address is used.

                      You could just install the freebsd port onto pfsense if you have no other say linux box on this "dc" vlan that is one of your lan networks.

                      You could also get sneaky and set van IDs in your arp scan to see if you can jump vlans. Which would be bad in a DC..

                      But also just running a packet capture looking for arps on this network and see if you see any arps from stuff that is not yours on this dc "lan" network would be way to check as well.

                      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 2.7.2, 24.11

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                      • L
                        lewis
                        last edited by

                        Using arp, I see only my own stuff. I'll spend more time on this once I get everything else done. That way, it'll be a complete working config and hopefully, very secure as promised.

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @lewis
                          last edited by

                          @lewis yeah arp scanning is very fast, and most anything is going to answer an arp, even if firewall blocking all protocols and ping, etc. Only problem with that sort of scan is you have to be on the same L2..

                          But for what your looking for its prob more in line with what your looking to do..

                          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 2.7.2, 24.11

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                          • L
                            lewis @johnpoz
                            last edited by

                            @johnpoz said in Unknown servers on VLAN:

                            @lewis yeah arp scanning is very fast, and most anything is going to answer an arp, even if firewall blocking all protocols and ping, etc. Only problem with that sort of scan is you have to be on the same L2..

                            But for what your looking for its prob more in line with what your looking to do..

                            Yes, basically just wanting to make sure I have my own relatively secure LAN (VLAN) network.

                            I'll do it again once everything is up.

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