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    Installing pfSense with a layer 3 switch

    Scheduled Pinned Locked Moved Problems Installing or Upgrading pfSense Software
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    • johnpozJ
      johnpoz LAYER 8 Global Moderator
      last edited by

      "My initial setup does work pointing to the switch."

      And that is a BROKE setup plain and simple..  You have a asynchronous routing, as in my 2nd pic.  While it may work depending on your traffic flows and firewall rules and or setting to be less strict its BAD practice!!

      You should always avoid this sort of setup, along with avoiding any sort of hair pins where ever possible..  Sometimes you have to live with a hairpin when you allow traffic between vlans that are on the same physical nic.  But all vlans and or subinterface always remove overall performance of that nic..

      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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      • C
        coxhaus
        last edited by

        Well I have tried /30 mask.  pfsense does not seem to talk to the switch.  I can not ping either way.

        pfsense–----------------------------------VLAN10----------------layer 3 switch
          192.168.10.1/30                                192.168.10.2/30

        The other networks and VLANs are on the switch untouched.  The only thing I did was change the LAN interface IP 192.168.10.1/30 and the switch VLAN 10 to 192.168.10.2/30.  Have you tried this with your SG300 switch?

        If I use the /24 mask all works. It even works with no other devices in VLAN10 other than pfsense and the layer 3 switch.

        I reinstalled pfsense and have the same problem.

        Now I have a problem on the new install with the resolver.  I think it was working on the first install.  The new install seems to have issues with my routed networks and DNS.  I turned off resolver and turned on the forwarder and all works.  I am going to keep looking.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          you could use a /8 for your transit network if you wanted.  As long as no end use devices are on the network then its a "transit" network.  /30 is just common since its only got 2 IPs.. A network that connects 2 or more routers is a transit network..  When you put devices on such a network and have different paths for how traffic goes to and from that device is when you have asynchronous routing. Which is BAD thing, especially when it comes to stateful firewalls like pfsense.  Clients don't always like the going to mac A, and coming back from mac B either..  Like I said its BAD and Broken setup..

          /29 is also common since you have 6 IPs and allow for hsrp on both sides of the transit with HA pairs with your routers with your physical IPs and VIPs on both sides..  You can use any sized network you want/need as your transit.

          As to have I done this with my sg300.. I do not have my sg300 currently in L3 mode - I have no reason for downstream networks in my home setup, while I have thought of it for performance since my pfsense is VM on some aging hardware. But yes I have done it when I was playing with the switch when I first got it an had it in L3 mode.  But this is something that that is done every single day in any network anywhere on the planet.  As stated this is basic IP routing.

          You clearly show a workstation on your 192.168.10 network, pointing to to your switch on that network, while the gateway off to the internet is pfsense on that same 192.168.10 network - that is NOT a transit network..  And if you just tried changing the mask to /30 you would only have 2 address in that network… So you could NOT have any workstations on 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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          • C
            coxhaus
            last edited by

            For home use I find separating  devices from my server and workstations works better.  I also have a music, LAN and guest network. I have 3 wireless APs with 2 common SSIDs one for LAN and one for guest to allow roaming and they support my network by putting the user in the guest VLAN or the LAN VLAN based on logon.

            How all this started is a friend brought over a broken laptop for me to fix and it infected my music server which I had spent weeks putting CDs on.  I now have a music VLAN separate from all others.  This prompted me to build a guest VLAN.  I still needed to share printers and certain video stuff which friends bring over.  So I needed ACLs to share these devices to my guest network and my multi VLAN network was born using IP networks.

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            • johnpozJ
              johnpoz LAYER 8 Global Moderator
              last edited by

              I have multiple vlans and physical networks - agreed this is a good setup even for a home.  But I just let pfsense be my firewall/router between all my segments.  I have no need for a L3 switch in my home network.. Pfsense is more than capable or routing the traffic..  If I really needed the full gig between segments I would update my hardware vs running L3 downstream and loosing my firewall between the segments.

              My pfsense vm running on a old HP N40L can do 400-500mbps between the segments..  Which is good enough for my wifi that is for sure.. My workstation on the same segment as the stuff I work do..  The stuff on the other segments would never need to make sure they have full 1gig routed/firewalled… Internet is only 80mbps for gosh sake...

              My guest wifi is completely isolated, if you want to get on my normal wifi, that is still isolated from my other networks you need eap-tls setup..  I completely get the use and commend proper network segmentation and firewalls in a home setup..

              But if I was going to use a downstream router, I sure and the hell would not set up asynchronous routing - nor would I hairpin connections ;)

              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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              • DerelictD
                Derelict LAYER 8 Netgate
                last edited by

                I wouldn't use a layer 3 switch for that. Or at least for the segments you really want to lock down like the guest network.

                This is basic IP routing, bro. Only you can decide how you want your network topology laid out. You can have some networks on the layer 3 switch, relying on whatever its packet filtering capabilities are and some networks on pfSense using its full stateful firewall capabilities. You can have some VLANs with SVIs on the switch and some without SVIs for which pfSense provides all the Layer 3 services. It's really up to you.

                But you really can't put hosts on the same network that connects the two routers unless you want to maintain routing tables on those hosts.

                Well I have tried /30 mask.  pfsense does not seem to talk to the switch.  I can not ping either way.

                Then you did it wrong, plain and simple. Post details of what you have actually done, not what you think you've done because it's not what you think you've done or it would be working.

                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

                  you really can't put hosts on the same network that connects the two routers unless you want to maintain routing tables on those hosts.

                  Exactly!!!! Very cleanly stated…

                  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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                  • DerelictD
                    Derelict LAYER 8 Netgate
                    last edited by

                    I've been meaning to do this one for a while:

                    pfSense-Layer-3-Switch.png
                    pfSense-Layer-3-Switch.png_thumb

                    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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                    • C
                      coxhaus
                      last edited by

                      I use pfsense for a fast router firewall NAT device.  I like the idea of snort.

                      I want to keep all my VLAN networks on the switch.  When I create VLANs I always assign an IP network to each VLAN.  ACLs provide enough control for me and my network.  I  have 3 Cisco WAP321 which dumps users into a guess network or a LAN network.  This works great for me. I am able to feed multiple VLANs to one router VLAN on the layer3 switch to feed the router. The SG300-28 has a 17 GIG backplane so it can run faster than any internet connection I would have.  I only have a 300megabit connection.  I just want the fastest firewall I can run on the front door to the internet.  pfSense is on the table now.

                      I am not saying pfsense has a problem with a /30 mask. It could be the SG300-28 switch.  It is why I asked johpoz whether he had tried it as he owns an Cisco SG300 switch also.  I have posted a question on the Cisco small business web site to ask if there is an issue.

                      I took a working pfsense router 192.168.10.1/24 mask plugged into a router VLAN on the SG200-28 switch defined with a /24 mask. It was working and is my current config I am using.  I changed the VLAN IP to 192.168.10.2/30 on the switch and I changed the default route to 192.168.10.2/30 also. I then ran 2 on the console for pfsense to change the LAN IP to 192.168.10.1/30.  I could not ping from the switch using ping on the switch to pfsense.  I could not ping from pfsense to the switch.  The switch port used is an access port defined to the router VLAN. It is the same port used for the /24 mask which works.  This sounds basic so I was looking for confirmation from john since he recommended using a /30 mask on this thread.

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                      • DerelictD
                        Derelict LAYER 8 Netgate
                        last edited by

                        Neither the Cisco SG nor pfSense has any problems with a /30 netmask. Guaran-effing-teed. You did something wrong.

                        And it doesn't matter one bit what netmask you use. All that matters is that there are no hosts on the transit network that you expect to route properly unless you maintain a proper routing table on that host.

                        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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                        • C
                          coxhaus
                          last edited by

                          The net mask does make a difference.  It works with a /24 mask and does not work with /30 mask.  I do not run any clients in my router VLAN.  The idea of the router VLAN is to isolate from the broadcast domain, default VLAN, Windows chatter, etc. I do not want the router waiting for any local traffic not destined for the internet.

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                          • DerelictD
                            Derelict LAYER 8 Netgate
                            last edited by

                            Dude. You did something wrong. No way the Cisco or pfSense has a problem with /30. If it was /31 maybe. /30 no way. Look at your config again.

                            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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                            • C
                              coxhaus
                              last edited by

                              When I have another free evening.  I spent about 5 hours going over everything.  I even reinstalled pfsense.

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                              • DerelictD
                                Derelict LAYER 8 Netgate
                                last edited by

                                Chasing ghosts. And that was after changing the netmask on both ends from /29 to /30 - no reboots just change and apply.

                                ![Screen Shot 2016-01-31 at 4.25.48 PM.png](/public/imported_attachments/1/Screen Shot 2016-01-31 at 4.25.48 PM.png)
                                ![Screen Shot 2016-01-31 at 4.25.48 PM.png_thumb](/public/imported_attachments/1/Screen Shot 2016-01-31 at 4.25.48 PM.png_thumb)
                                ![Screen Shot 2016-01-31 at 4.25.38 PM.png](/public/imported_attachments/1/Screen Shot 2016-01-31 at 4.25.38 PM.png)
                                ![Screen Shot 2016-01-31 at 4.25.38 PM.png_thumb](/public/imported_attachments/1/Screen Shot 2016-01-31 at 4.25.38 PM.png_thumb)
                                ![Screen Shot 2016-01-31 at 4.27.39 PM.png](/public/imported_attachments/1/Screen Shot 2016-01-31 at 4.27.39 PM.png)
                                ![Screen Shot 2016-01-31 at 4.27.39 PM.png_thumb](/public/imported_attachments/1/Screen Shot 2016-01-31 at 4.27.39 PM.png_thumb)

                                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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                                • C
                                  coxhaus
                                  last edited by

                                  You need to be changing the LAN side em1 not em0.  This means all your local networks are routed on the LAN side. And you need static routes for all local traffic. I guess it could be an alias.

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                                  • DerelictD
                                    Derelict LAYER 8 Netgate
                                    last edited by

                                    em0 is my LAN side. Neither device has a problem with /30, regardless.

                                    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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                                    • C
                                      coxhaus
                                      last edited by

                                      Sounds good.  I don't know why they will not link up with /30 mask for me.  It works with a /24 mask so there is not a rush.

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                                      • johnpozJ
                                        johnpoz LAYER 8 Global Moderator
                                        last edited by

                                        You can use whatever mask you want for the transit - the point is there can be no clients on the transit or you will end up with problems unless you create host routes on them for the networks in 2 different directions.

                                        The fact that you think a /30 is a problem for these devices is beyond nonsense.. As derelict said you did something wrong..

                                        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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                                        • C
                                          coxhaus
                                          last edited by

                                          @johnpoz:

                                          You can use whatever mask you want for the transit - the point is there can be no clients on the transit or you will end up with problems unless you create host routes on them for the networks in 2 different directions.

                                          The fact that you think a /30 is a problem for these devices is beyond nonsense.. As derelict said you did something wrong..

                                          The /24 mask is more convenient so if you need to change the gateway to the static routes you can plug in a machine and make the change.  With a /30 mask there basically is no access to pfsense if something happens to your routing other than console from what I see.

                                          The question about the /30 mask can be answered by you since you have one of these SG300 switches.  Just set it up.  Please post the config on the SG300 and I will compare it to mine.

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                                          • DerelictD
                                            Derelict LAYER 8 Netgate
                                            last edited by

                                            Pertinent parts.

                                            vlan database
                                            vlan 1000,2000

                                            ip dhcp server
                                            ip dhcp pool network TEST_LAYER3
                                            address low 172.28.1.65 high 172.28.1.254 255.255.255.0
                                            default-router 172.28.1.1
                                            dns-server 192.168.223.1
                                            exit

                                            interface vlan 1000
                                            name TRANSIT
                                            ip address 192.168.230.2 255.255.255.252
                                            !

                                            interface vlan 2000
                                            name TEST_LAYER3
                                            ip address 172.28.1.1 255.255.255.0
                                            !

                                            interface gigabitethernet46
                                            description ROUTER_LAN
                                            switchport mode general
                                            switchport general allowed vlan add 1000 tagged
                                            switchport general acceptable-frame-type tagged-only
                                            !

                                            Not a lot to it. On pfSense I just created interface TRANSIT on vlan1000 as 192.168.230.1/30, a gateway for 192.168.230.2, and a static route for 172.28.0.0/16 to the gateway.

                                            Then I passed ICMP any source any dest TRANSIT address on the TRANSIT interface. Could ping across in both directions and from a host on vlan 2000.

                                            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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