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    PfSense firewall BEHIND router

    Scheduled Pinned Locked Moved Problems Installing or Upgrading pfSense Software
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    • P
      phil.davis
      last edited by

      You must already have the port(s) for the game server forwarded from the DSL modem to 192.168.1.4 (the original game server IP). So we can take advantage of that to make things a little easier.

      pfSense WAN and LAN sides MUST be different subnets. To make life easy for you, make your pfSense WAN IP the same as the old game server IP - 192.168.1.4

      Now pfSense WAN will be receiving incoming connections on the game port(s).

      Change pfSense LAN to be something else - e.g. 192.168.2.1/24

      Change the game server to be in that new LAN subnet - e.g. 192.168.2.4

      In pfSense, Firewall->NAT, Port Forward, add port forward(s) to forward the needed game ports from WAN to 192.168.2.4

      –------------------
      Extra bit:
      In general I would avoid the 192.168.1.0/24 subnet, because it is used by default by so many devices/routers/WiFi... You save yourself future pain from conflicts by picking some "random" piece of private IPv4 address space to use, in the hope that you will not have future accidental conflicts when you add a VPN connection to your mates house, or the office, or...

      If you want to renumber your whole network, then go for it - pick something like 192.168.42.x/24 for the LAN side of your DSL modem, then 192.168.43.x/24 for the LAN side of your pfSense...

      But of course that means you have to change addresses and port forwards in the DSL modem as well as pfSense etc.

      As the Greek philosopher Isosceles used to say, "There are 3 sides to every triangle."
      If I helped you, then help someone else - buy someone a gift from the INF catalog http://secure.inf.org/gifts/usd/

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      • M
        Mr. Magoo
        last edited by

        Thank you for the quick and detailed reply.  This is a new DSL modem that my ISP just installed.  I have never even attempted to log into it.  I do not know how it assigns the IP's to the ethernet ports.

        I guess it just knows, or Steam knows, how to punch through the modem for the game server.  Without the pfSense in the way it works fine.

        To change my game server to 192.168.2.1/24, will Windows7 automatically detect the new LAN?  I know in Win98 I could manually put in the IP and subnet stuff.  Win7 seems to just do stuff automatically and leave me out of the loop.

        I will have to wait for the weekend to enact the changes, after which I will leave feedback.

        ~Mr. Magoo

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        • P
          phil.davis
          last edited by

          Yes, I expect Steam knows how to punch out through the upstream modem/router(s) - probably it contacts a known server out on the internet.

          In that case, you just need to get pfSense working

          1. Make the pfSense LAN 192.168.2.1/24
          2. Enable the DHCP server on pfSense LAN and let it give out IP addresses in its default range.
          3. Let the client system with the game just get an IP by DHCP. Windows7 will just learn the new subnet and gateway.

          As the Greek philosopher Isosceles used to say, "There are 3 sides to every triangle."
          If I helped you, then help someone else - buy someone a gift from the INF catalog http://secure.inf.org/gifts/usd/

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          • M
            Mr. Magoo
            last edited by

            Phil,

            Thank you for the reply.  The last time I tried to set up pfSense it would not let me set the LAN to DHCP.  It kept telling me it had to be static.  I don't know if this had to do with my WAN settings being on the same subnet.  I will try it again this weekend.

            ~Magoo

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            • D
              divsys
              last edited by

              I think what Phil is suggesting here is to enable the "Services->DHCP Server" for the static LAN interface.

              That way pfSense will have a fixed LAN address (192.168.2.1 within a /24 subnet) and can supply other 192.168.2.??? addresses to everything else you have on that LAN network.
              Your PC's, and other devices may need to reboot/reconnect to get a new address at first, but it should be pretty seamless.

              As Phil mentioned, you definitely can't have LAN and WAN on the same subnet.

              -jfp

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              • ?
                Guest
                last edited by

                This is a new DSL modem that my ISP just installed.

                A router is doing SPI/NAT and a modem not! This is your real problem here as I see it right.
                You could try out to set your ISP router into the so called "bridge mode" that this router is
                acting then likes a pure modem. This would also my personally first choice to try out.

                Internet –- modem --- pfSense --- small switch --- LAN clients
                                                  |
                                                  |opened & forwarded ports
                                                  |DMZ
                                                  |
                                                  Game Server

                This might be the most common option to handle and solve your "problem" in my eyes.

                The second choice would be to create a router cascade or also called "double NAT" situation.
                You set up on your ISP router the following things:
                Network: 192.168.1.0/24 (255.255.255.0)
                IP Address: 192.168.1.1/24 static or fix
                DHCP: off

                pfSense WAN:
                Network:192.168.1.0/24 (255.255.255.0)
                IP Address: 192.168.1.2/24 static or fix
                DHCP: off
                DNS: 192.168.1.1/24

                pfSense LAN:
                Network:192.168.5.0/24 (255.255.255.0)
                IP Address: 192.168.5.1/24
                DHCP: on IP range from 192.168.5.2 - 192.168.5.254/24
                DNS: 192.168.1.2/24

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                • M
                  Mr. Magoo
                  last edited by

                  It worked!!!!

                  Thank you both so much.  I still have to port forward the game but at least now the Win7 Client is able to access the internet from behind the firewall.

                  I set WAN to 192.168.1.4 and LAN to 192.168.2.1 and let LAN act as DHCP server.  It took a reboot, but after that everything seems fine.

                  Now I have to figure out how to ban certain IP's (cheaters) that Steam/Valve/Gearbox won't do anything about.

                  Thanks again.

                  ~Magoo

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                  • M
                    Mr. Magoo
                    last edited by

                    Okay,

                    Now I have the game server up and going.  Firewall question …

                    I have made aliases with all the IP's that I would like to ban.  I have called them:

                    A_cheaters
                    B_cheaters
                    C_cheaters
                    etc.

                    In order to ban these IP's from communicating with my server I will place a firewall rule for each one of them.  For this to work I will put the rule on?...

                    Rule on LAN source - A_cheaters, destination?

                    I am not sure if the destination should be LAN address or LAN net.  If I only ban UDP protocol will this speed up the throughput for less lag, or should I leave it to ban any protocol?

                    Or is the above totally off base, and the ban should go on the WAN?

                    ~Magoo

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      If you do not want those IPs in your aliases to get to your server through your forwards.  Then you want to put them on rules on your wan BEFORE you allow the traffic in on your forward.

                      Or they need to be included in your NAT where your source is a NOT, and then an aliases listing the IPs you don't want in.  That is difficult with multiple aliases.

                      When you put a rule on the lan, that would be traffic outgoing from your lan.  So if your server was going to create the connection to those IP then you would want them on the LAN side of it.  But if you allow them in, this will create a state.  And then your server would be allowed to answer no matter what rule you had on the LAN side saying not to talk to those IPs.

                      Rules are looked at INBOUND to an interface…  Top down, first rule wins.

                      So you have to look to where pfsense would first see the SYN, ie the start/request for a conversation.  For stuff inbound into your network starting conversations this is on your WAN..  For your devices on your LAN starting conversations outside of LAN, this would be the LAN 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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                      • M
                        Mr. Magoo
                        last edited by

                        Thank you for the reply.

                        To see if I understand, if I want to ban "A_cheaters" alias list I would put:

                        Firewall –> Rules --> WAN --> Add new rule -->Block, WAN, IPv4, any protocol, source = single host or alias-A_cheaters, destination = any?

                        If I wanted to further ensure that my server doesn't make an outgoing connection to these I would put the same rule on the LAN where source = ?, destination = A_cheaters.

                        If my computer does connect to any of these IP's from my end, then it will negate the incoming firewall blocking rule.

                        Correct?

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          If you don't want your servers connecting to those IPs, ie create the connection to them (not answer) then yes rule would go on your LAN.  Not sure where your server would ever make a connection to them??

                          As your wan rule yeah putting those blocks on the top of your rules list would prevent then from hitting any allow rules for your forwards.

                          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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                          • M
                            Mr. Magoo
                            last edited by

                            Ok thanks,  I think I have it.  I'm still not sure what the destination for the WAN rule should be, so I set it to any.

                            Steam has been allowing cheaters to still join my server by routing them through a Valve server.  That is why I am interested in the outbound blocks as well.  The game I am hosting is peer-to-peer.  I have noticed that banned IP's still connect via Valve.  If needed, I will ban the Valve servers to keep them from allowing the cheaters in.

                            ~Magoo

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                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              Your destination would normally be your WAN IP..  Since to be honest that is the ONLY IP it could ever be dest for.

                              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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