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    UDP broadcasts to WAN

    Scheduled Pinned Locked Moved NAT
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      "The bridge might have a connection to the problem."

      Yeah think ;)  Broadcast traffic is not sent out to other networks no matter what routing you have in place.

      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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      • R
        ristosu
        last edited by

        Well, that's what I thought, but I was obviously wrong.

        The bridge is there to allow one DHCP to serve both LAN interfaces, WAN is not part of it. And the strange packets look like routed: the source MAC is that of the WAN.

        Risto

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          Again packets that are broadcast would not go out to another network.  Unless they were bridged, or maybe IGMP proxy - did you have that setup?

          Can you post a sniff of this traffic you were seeing going out the wan?

          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
            doktornotor Banned
            last edited by

            @ristosu:

            The bridge is there to allow one DHCP to serve both LAN interfaces

            Which is totally unneeded. That one DHCP can serve two (or really any number of) different subnets just fine and the firewall will route packets between those just fine as well.

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            • R
              ristosu
              last edited by

              @johnpoz:

              Again packets that are broadcast would not go out to another network.  Unless they were bridged, or maybe IGMP proxy - did you have that setup?

              No.
              @johnpoz:

              Can you post a sniff of this traffic you were seeing going out the wan?

              23:54:18.884766 00:0d:b9:17:cb:28 > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800), length 92: (tos 0x0, ttl 128, id 1685, offset 0, flags [none], proto UDP (17), length 78)
                  192.168.1.31.137 > 192.168.1.255.137: NBT UDP PACKET(137): QUERY; REQUEST; BROADCAST
              where 00:0d:b9:17:cb:28 is WAN (vr0) MAC,
              LAN (bridge0) IP is 192.168.1.7,
              WAN (vr0) IP is 80.x.x.x (DHCP).
              @doktornotor:

              Which is totally unneeded. That one DHCP can serve two (or really any number of) different subnets just fine and the firewall will route packets between those just fine as well.

              I agree. But my next goal would be to serve 20 VLANs.

              Risto

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                So your going to bridge 20 vlans together??  What does that have to do with bridging interfaces for dhcp?

                You must have something F'd up in your bridge if your sending out broadcast out your wan..  Or you installed something on pfsense to send it out, or is this a VM running on virtualbox and you didn't remove the windows bindings from the interface and that is windows sending that out.  Is pfsense vm??  OR is this hardware?  Ah from mac looks like PC Engines..

                Again lets say this one more time so you understand it BROADCAST traffic is NOT routed.. Pfsense would not get a FF:FF packet on its lan and say oh lets send this out my wan.  It wouldn't happen!  Unless you have some sort of bridge, or some kind of broadcast proxy, etc.

                Did you install say samba on pfsense?  So sniff on your lan at same time your sniffing wan, where is the broadcast coming from if you say pfsense is forwarding it.

                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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                • R
                  ristosu
                  last edited by

                  @johnpoz:

                  So your going to bridge 20 vlans together??  What does that have to do with bridging interfaces for dhcp?

                  Yes. I want to avoid configuring 20 subnets. Perhaps I could try one subnet for the vlans and one for the wlan.
                  @johnpoz:

                  You must have something F'd up in your bridge if your sending out broadcast out your wan..  Or you installed something on pfsense to send it out, or is this a VM running on virtualbox and you didn't remove the windows bindings from the interface and that is windows sending that out.  Is pfsense vm??  OR is this hardware?  Ah from mac looks like PC Engines..

                  Yes, it definitely seems to be caused by the bridge: I took it away, and the symptoms ceased. It is a PC Engines Alix 6b2.
                  @johnpoz:

                  Again lets say this one more time so you understand it BROADCAST traffic is NOT routed.. Pfsense would not get a FF:FF packet on its lan and say oh lets send this out my wan.  It wouldn't happen!  Unless you have some sort of bridge, or some kind of broadcast proxy, etc.

                  Unless there's a bug in it. Well, I don't have any such daemons, just the bridge. But bridged traffic should have the original sender's MAC address. I've changed these two system tunables from their defaults: net.link.bridge.pfil_member=0, net.link.bridge.pfil_bridge=1. And I've defined all bridge ports as edge and private: I don't want them to communicate to each other.
                  @johnpoz:

                  Did you install say samba on pfsense?  So sniff on your lan at same time your sniffing wan, where is the broadcast coming from if you say pfsense is forwarding it.

                  No Samba. I've seen it coming from a windows box on the lan.

                  Thanks for your comments so far.

                  Risto

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                  • D
                    doktornotor Banned
                    last edited by

                    @ristosu:

                    @doktornotor:

                    Which is totally unneeded. That one DHCP can serve two (or really any number of) different subnets just fine and the firewall will route packets between those just fine as well.

                    I agree. But my next goal would be to serve 20 VLANs.

                    So, you are going to bridge 20 VLANs? Why bother in the first place? Just get a dumb switch and put all on a single LAN. WTF. This must be some disease with the bridging. Lets bridge VLANs, lets bridge WLAN with wired LAN, lets bridge 10 ports to waste hardware trying to turn a router into a dumb switch.

                    ??? :o

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                    • R
                      ristosu
                      last edited by

                      @doktornotor:

                      So, you are going to bridge 20 VLANs? Why bother in the first place? Just get a dumb switch and put all on a single LAN. WTF. This must be some disease with the bridging. Lets bridge VLANs, lets bridge WLAN with wired LAN, lets bridge 10 ports to waste hardware trying to turn a router into a dumb switch.

                      ??? :o

                      There is a reason for everything. In this case I want to separate the vlans (private bridge ports) so they don't see each other. There is no excuse for pfsense's bridge not working as it should.

                      Risto

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                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        Yes. I want to avoid configuring 20 subnets.

                        Another one who thinks administering a network isn't going to be work.  It boggles the mind.

                        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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                        • DerelictD
                          Derelict LAYER 8 Netgate
                          last edited by

                          There is a reason for everything. In this case I want to separate the vlans (private bridge ports) so they don't see each other. There is no excuse for pfsense's bridge not working as it should.

                          What you're doing is nonsensical.  I don't think you quite understand what a "bridge" does.

                          There are other, better ways to do what you're trying to do.  One being a separate VLAN interface for each VLAN like any sane person would do.  Another would be private VLAN edge (protected) ports on a switch with everyone on the same VLAN.  Cisco 2950s do this 10/100 and are essentially free.  Most "cheap" web-managed switches (trendnet, d-link, TP-link, etc) can fake this with "asymmetric VLANs".

                          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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                          • johnpozJ
                            johnpoz LAYER 8 Global Moderator
                            last edited by

                            "I want to separate the vlans (private bridge ports) so they don't see each other"

                            Huh - so you don't want clients seeing each other but you want to connect the vlans together with a bridge?  Lets taking bridging to its simplest level.  Packets come in one interface, they get sent out all bridge members interfaces.  So if you want devices on different vlans not to see each other - why would you bridge them?

                            Sure you can setup firewall rules between a bridge and isolate them that way - but if you don't want them to see each other or only have a few exceptions - why make it a bridge in the first place?

                            If you have 20 vlans, then setup 20 vlans and 20 network segments and 20 dhcp servers.  That is the way you would do it if you ask me.. Or if you don't want to setup dhcp servers, then send them to a dhcp server that supports different scopes, etc.  I don't think pfsense allows for serving up multiple scopes, you can have multiple pools but don't think it can serve up multiple segments off one server instance?

                            Im with Derelict here, we all like shortcuts to min admin - but running a network takes work, if it didn't than any user could do it ;)

                            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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                            • R
                              ristosu
                              last edited by

                              @Derelict:

                              What you're doing is nonsensical.  I don't think you quite understand what a "bridge" does.

                              I think I do. I'm only trying to use bridge config here as a means to achieve my goal, which I've hopefully explained already. As the bridge ports are all private, it's no usual bridge.
                              @Derelict:

                              There are other, better ways to do what you're trying to do.  One being a separate VLAN interface for each VLAN like any sane person would do.  Another would be private VLAN edge (protected) ports on a switch with everyone on the same VLAN.  Cisco 2950s do this 10/100 and are essentially free.  Most "cheap" web-managed switches (trendnet, d-link, TP-link, etc) can fake this with "asymmetric VLANs".

                              There are always different ways of doing things. I was disappointed, when I understood, that my switch doesn't support that.
                              @johnpoz:

                              "I want to separate the vlans (private bridge ports) so they don't see each other"

                              Huh - so you don't want clients seeing each other but you want to connect the vlans together with a bridge?  Lets taking bridging to its simplest level.  Packets come in one interface, they get sent out all bridge members interfaces.  So if you want devices on different vlans not to see each other - why would you bridge them?

                              The bridge in mostly for dhcp, but it should shorten the nat table, too. And, as always, there are historical reasons…
                              @johnpoz:

                              Sure you can setup firewall rules between a bridge and isolate them that way - but if you don't want them to see each other or only have a few exceptions - why make it a bridge in the first place?

                              There is a simple setting in pfSense when creating the bridge: private port.
                              @johnpoz:

                              If you have 20 vlans, then setup 20 vlans and 20 network segments and 20 dhcp servers.  That is the way you would do it if you ask me.. Or if you don't want to setup dhcp servers, then send them to a dhcp server that supports different scopes, etc.  I don't think pfsense allows for serving up multiple scopes, you can have multiple pools but don't think it can serve up multiple segments off one server instance?

                              As long as it looks like I can make this work with quite short, and thus readable, config, I try to do it my way, then probably yours.
                              @johnpoz:

                              Im with Derelict here, we all like shortcuts to min admin - but running a network takes work, if it didn't than any user could do it ;)

                              Me too :)

                              Risto

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                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by

                                I was disappointed, when I understood, that my switch doesn't support that.

                                Get one that does?  Like I said, Cisco 2950s are essentially free.

                                There is a simple setting in pfSense when creating the bridge: private port.

                                Yes, there is.

                                So you have created a bridge containing:
                                eth0_vlan10
                                eth0_vlan11
                                eth0_vlan12
                                …
                                eth0_vlan29

                                All those interfaces are marked as "private" in the bridge config

                                You assigned your pfSense LAN interface to BRIDGE0

                                You created a single subnet on LAN and a single DHCP server on LAN

                                You have pass any any rules and good outbound NAT on LAN and for LAN's subnet

                                You have eth0 connected to a switch port with tagged VLANs 10-29

                                You have stations connected to untagged ports, one each, VLANs 10-29 (20 untagged ports)

                                And what exactly is not working?

                                What additional steps or config changes did you do?

                                I have never tried that private member setting in 2.2.  I'll try it tonight.

                                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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                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator
                                  last edited by

                                  "I was disappointed, when I understood, that my switch doesn't support that."

                                  Get a better switch ;)  Its not like you need a 250K nexus dual core setup do something as basic as private vlans.  My <$200 cisco sg300 does it for sure.

                                  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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                                  • R
                                    ristosu
                                    last edited by

                                    @Derelict:

                                    Get one that does?  Like I said, Cisco 2950s are essentially free.

                                    I'll keep it in mind.
                                    @Derelict:

                                    So you have created a bridge containing:
                                    eth0_vlan10
                                    eth0_vlan11
                                    eth0_vlan12
                                    …
                                    eth0_vlan29

                                    All those interfaces are marked as "private" in the bridge config

                                    You assigned your pfSense LAN interface to BRIDGE0

                                    You created a single subnet on LAN and a single DHCP server on LAN

                                    You have pass any any rules and good outbound NAT on LAN and for LAN's subnet

                                    You have eth0 connected to a switch port with tagged VLANs 10-29

                                    You have stations connected to untagged ports, one each, VLANs 10-29 (20 untagged ports)

                                    And what exactly is not working?

                                    UDP broadcasts from lan (LOCAL, see below) subnet are getting through out of WAN. (I am able to stop them by saying LOCAL to !LOCAL instead of any to any.)
                                    @Derelict:

                                    What additional steps or config changes did you do?

                                    Essentially everything is as you say. With two more things. BRIDGE0 is actually opt2 named LOCAL. LAN is left separate for switch admin access. And there is a second wan (3G, tier 2), wan group, consisting of these two, and it is given as Gateway in the any to any rule.
                                    @Derelict:

                                    I have never tried that private member setting in 2.2.  I'll try it tonight.

                                    Thanks for your interest.

                                    Risto

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                                    • DerelictD
                                      Derelict LAYER 8 Netgate
                                      last edited by

                                      @ristosu:

                                      @johnpoz:

                                      Again packets that are broadcast would not go out to another network.  Unless they were bridged, or maybe IGMP proxy - did you have that setup?

                                      No.
                                      @johnpoz:

                                      Can you post a sniff of this traffic you were seeing going out the wan?

                                      23:54:18.884766 00:0d:b9:17:cb:28 > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800), length 92: (tos 0x0, ttl 128, id 1685, offset 0, flags [none], proto UDP (17), length 78)
                                          192.168.1.31.137 > 192.168.1.255.137: NBT UDP PACKET(137): QUERY; REQUEST; BROADCAST
                                      where 00:0d:b9:17:cb:28 is WAN (vr0) MAC,
                                      LAN (bridge0) IP is 192.168.1.7,
                                      WAN (vr0) IP is 80.x.x.x (DHCP).
                                      @doktornotor:

                                      Which is totally unneeded. That one DHCP can serve two (or really any number of) different subnets just fine and the firewall will route packets between those just fine as well.

                                      I agree. But my next goal would be to serve 20 VLANs.

                                      Risto

                                      You need to double check all the facts you assert in this post.  Don't just gloss over this request and say "yeah, it's just like that" really go back and look again at everything.

                                      What interface was that capture taken on?

                                      Please provide a few more, captured on the WAN interface.  Preferably some generic broadcasts like ARP, DHCP, etc.  I don't have any windows CIFS hosts to test with - at least not readily.

                                      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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                                      • DerelictD
                                        Derelict LAYER 8 Netgate
                                        last edited by

                                        And, real quick, be sure one of your LOCAL VLANs isn't mistakenly created on vr0 instead of your tagged LOCAL interface.  It's easy to do.

                                        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
                                          ristosu
                                          last edited by

                                          @Derelict:

                                          And, real quick, be sure one of your LOCAL VLANs isn't mistakenly created on vr0 instead of your tagged LOCAL interface.  It's easy to do.

                                          [2.2-RELEASE][admin@pfSense.localdomain]/root: ifconfig | grep vr0
                                          vr0: flags=8843 <up,broadcast,running,simplex,multicast>metric 0 mtu 1500
                                                  inet6 fe80::20d:b9ff:fe17:cb28%vr0 prefixlen 64 scopeid 0x1 
                                          [2.2-RELEASE][admin@pfSense.localdomain]/root:</up,broadcast,running,simplex,multicast> 
                                          

                                          No, it isn't. Good point, though.

                                          Risto

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                                          • R
                                            ristosu
                                            last edited by

                                            @Derelict:

                                            What interface was that capture taken on?

                                            Actually on another host on wan side. But the sender's MAC is pfSense's WAN.
                                            @Derelict:

                                            Please provide a few more, captured on the WAN interface.  Preferably some generic broadcasts like ARP, DHCP, etc.  I don't have any windows CIFS hosts to test with - at least not readily.

                                            I'll try tomorrow.

                                            Risto

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