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    Simplied method of preventing inter-VLAN communication

    Scheduled Pinned Locked Moved Firewalling
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    • Cloudless Smart HomeC
      Cloudless Smart Home
      last edited by Cloudless Smart Home

      still blocking internet access on my home assistant on this IoT vlan. thought I had it sorted out, and haven't made the changes answered above, but am I missing something? my home assistant can download updates or even reboot properly if this rfc1918 block rule is enabled, but it the setup I posted above does seem to work fine for the crypto vlan. it's so weird, because the rfc1918 is the only block rule on the IoT vlan, and I have the allow rule to the appropriate .1 address, same as crypto vlan.

      Screenshot 2023-01-18 at 7.13.15 PM.png

      Screenshot 2023-01-18 at 7.15.49 PM.png

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      • johnpozJ
        johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
        last edited by johnpoz

        @appleguy and where are you pointing for dns? If it was say the IP address of pfsense (rfc1918) on your iot network - you blocked it.. So yeah internet stuff not going to work via dns.

        Here is a what you might use for a typical locked down vlan.

        rules.jpg

        This allows talking to pfsense IP on this vlan for dns and ntp, and also allows clients on this network to ping pfsense IP (connectivity testing for example).

        But blocks all other access to any firewall IP - prevent access to gui on this network, or even say the wan IP (which is commonly public IP)..

        Blocks access access to any other local network/vlan - and then at the end allows internet.

        An intelligent man is sometimes forced to be drunk to spend time with his fools
        If you get confused: Listen to the Music Play
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        • Cloudless Smart HomeC
          Cloudless Smart Home @Cloudless Smart Home
          last edited by Cloudless Smart Home

          @johnpoz

          Screenshot 2023-01-15 at 5.36.13 PM.png

          doesn't my first rule allow dns but just more open than it needs to be?

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
            last edited by

            @appleguy if that is where your pointing for dns - but that rule shows zero evaluations - see the 0/0 nothing has matched that rule.

            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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            • Cloudless Smart HomeC
              Cloudless Smart Home @johnpoz
              last edited by

              @johnpoz
              so should I say this firewall everywhere you said test address?

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
                last edited by johnpoz

                @appleguy huh.. for your iot vlan you would use your iot network and iot address where my rules have test.

                Where exactly is your home assistant pointing to for dns - it doesn't seem to be that 10.0.100.1 address (is this the iot pfsense IP?)

                It doesn't seem like anything on iot is trying to talk to that IP - since that rule has never even matched once..

                Oh - my bad, I mean your crypto address and network.

                home assistant on this IoT vlan

                What are the rules on this interface?? If something on your iot vlan is not getting internet - we need to see the rules on that interface.

                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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                • Cloudless Smart HomeC
                  Cloudless Smart Home @johnpoz
                  last edited by Cloudless Smart Home

                  @johnpoz I think because I took the screen shot before testing it. I am just updating everything like your example and see if that is better, (similar to previous answers) but I do better with pictures for sure ๐Ÿ˜‰

                  edit: order keeps changing on me because I didn't save the order
                  Screenshot 2023-01-18 at 10.09.19 PM.png

                  does that look right?

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                  • johnpozJ
                    johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
                    last edited by

                    @appleguy no - rules are evaluated top down, first rule to trigger wins and no other rules are evaluated.

                    If your dns is say 10.0.100.1 which is rfc1918 your first rule would prevent that access. So no dns.

                    edit - now that is wrong as well, since your block rules are below where you allow everything. Order matters..

                    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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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
                      last edited by

                      @appleguy yeah this better.. But not sure why your using "this firewall" for dns - while that can work.. Are you devices going to use every possible pfsense IP, or just the IP on that interface?

                      Normally you would only allow this network to talk to the IP of pfsense on that network for dns and ntp, ping, etc.

                      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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                      • Cloudless Smart HomeC
                        Cloudless Smart Home @johnpoz
                        last edited by Cloudless Smart Home

                        @johnpoz oh no, so change this firewall back to 10.0.100.1 on the first 3 rules? I think I need to allow for DHCP on the router too?

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
                          last edited by

                          @appleguy depends on what you want.. But your first rules should allow for dns and anything else you want to be allowed to the IP of pfsense on this interface. If you don't care about pinging pfsense, or ntp or even dns then that is not needed.

                          But normally clients only "need" to talk to 1 IP of pfsense, normally the IP of pfsense on that interface - "this firewall" is all IPs of pfsense, other vlans/networks - the wan IP, etc.

                          Its odd your not showing any hits on those rules 0/0 if you were actually using a Pfsense IP for dns - those should show some hits. Mine are all 0/0 on my test interface. Because I only use that interface for showing rules, etc. I don't really have a test 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 24.11 | Lab VMs 2.8, 24.11

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

                            @johnpoz here is an actual network of mine with devices on it.

                            guest.jpg

                            Notice my rule for dns is any for destination - I don't care where they talk for dns, which could be pfsense IP on this guest network or it might be 8.8.8.8 for example..

                            But see the order, I allow stuff I want that could be rfc1918 before I block rfc1918. In this case the "this firewall" rule is preventing access to say pfsense wan IP for the gui port or ssh, etc.

                            Just remember top down, first rule to trigger wins. Walk down your rules on what you want to allow, what you want to block, walking through the rules to see which rule would trigger..

                            In the case of these rules - I could prob just use wan address vs "this firewall" since what worried about is guest accessing say the public IP of pfsense for gui or ssh, all other IPs of pfsense are rfc1918.

                            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

                            Cloudless Smart HomeC 1 Reply Last reply Reply Quote 1
                            • Cloudless Smart HomeC
                              Cloudless Smart Home @johnpoz
                              last edited by

                              @johnpoz ok, loosened some back up a little. don't see any default rules for DHCP in protocols so DHCP should still work? I do DNS and DHCP from pfsense.

                              Screenshot 2023-01-18 at 10.27.48 PM.png

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                              • johnpozJ
                                johnpoz LAYER 8 Global Moderator @Cloudless Smart Home
                                last edited by

                                @appleguy dhcp is a hidden rule when you enable dhcp on an interface.

                                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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                                • JeGrJ
                                  JeGr LAYER 8 Moderator @Cloudless Smart Home
                                  last edited by

                                  @appleguy said in Simplied method of preventing inter-VLAN communication:

                                  @johnpoz ok, loosened some back up a little. don't see any default rules for DHCP in protocols so DHCP should still work? I do DNS and DHCP from pfsense.

                                  Screenshot 2023-01-18 at 10.27.48 PM.png

                                  @appleguy First three rules just need "CRYPTO addr" not "*" - no need for any in that case, as you'd normally only want them to reach pfSense for DNS and NTP or PING and leave anything other closed.

                                  Don't forget to upvote ๐Ÿ‘ those who kindly offered their time and brainpower to help you!

                                  If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

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                                  • Cloudless Smart HomeC
                                    Cloudless Smart Home @JeGr
                                    last edited by Cloudless Smart Home

                                    @jegr thanks again for all your help! finally got it right! wait, not *? does not mean inverted?

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                                    • S
                                      Stewart @johnpoz
                                      last edited by

                                      @johnpoz Is there a way to see the hidden rules? I've never really considered that there would be Firewall rules set up on an interface that we didn't know about. I've wondered from time to time how DHCP works even though traffic is denied.

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                                      • S
                                        Stewart @Cloudless Smart Home
                                        last edited by

                                        @appleguy This is how I have all my ports/VLANs set up by default. Similar to yours but I specify the destination and use external NTP.
                                        f159f222-8df2-4a64-90ca-499f53fe3048-image.png

                                        It's interesting to go back and see. Nothing's pinging the firewall or using DNS on this VLAN. That's OK. Nothing trying to get into the firewall. Also good. But something is trying to access other local IPs outside of the subnet? What're those cameras up to, I wonder? Glad I've got that block!

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                                        • Cloudless Smart HomeC
                                          Cloudless Smart Home @Stewart
                                          last edited by

                                          @stewart I like the vlan id in the name! gonna do that too ๐Ÿ˜

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                                          • S
                                            Stewart @Cloudless Smart Home
                                            last edited by

                                            @appleguy Makes it so much easier when you do that everywhere, even in the switches. You have full visibility and know right where you are instead of constantly needing to cross reference.

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