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    Problems to access Internet

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

      Why that won't work.

      So your on a box say 192.168.1.14 for example and your trying to go to pfsense.org.  so box at 1.14 says hey pfsense.org is on  69.64.6.21, that is not on any network connected to me - so it sends it to its gateway pfsense lan 192.168.1.1, it "routes" the traffic for  69.64.6.21 which is not on any of its interfaces so sends to its gateway - your modem "192.168.0.1"  this is all fine.

      So your "modem" now says hey your trying to get to  69.64.6.21, I will send that to my gateway (your isp) and NAT the traffic so it looks like it came from your "modems" public IP – lets call it 1.2.3.4..  So it sends it on its way to your isp with dst  69.64.6.21, and source ip 1.2.3.4 and stores the NAT of hey if your coming back from  69.64.6.21 to my IP of 1.2.3.4 I need to send you to 192.168.1.14.

      Problem is how does your modem know how to get to 192.168.1.0/24???  it has no interfaces on that network.  It only has interfaces on 192.168.0.0/24 and your public IP 1.2.3.4.  It needs to know how to get to the 192.168.1.0 network by sending it to pfsense wan interface on 192.168.0.2

      Without a route back to 192.168.1.0/24 your modem has no idea what to do with that traffic -- it needs a route!!  Which you make no mention of.  So what you were trying to setup would NEVER WORK.  It would not be intermittent, it wouldn't work.

      So unless your leaving off some details about running a routing protocol on pfsense and your "modem" so pfsense can share with your "modem" that to get to the 192.168.1.0/24 talk to my 192.168.0.2 interface your modem would not be able to send the return traffic from pfsense.org back to the client on 192.168.1.14

      edit: if you were NATTING on pfsense, then it would NAT all the traffic from 192.168.1.0/24 network to its 192.168.0.2 IP, but you clearly stated your NOT natting on pfsense.  If that is the case then you have to have a route on your "modem" on how to get to the 192.168.1.0/24 since pfsense did not NAT it to the network connected to your modem.  Your modem has no idea how to get there - so it would send traffic to its default gateway -- your isp.  How does it know to send to 192.168.0.2 to get to 192.168.1.14??

      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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      • W
        wallabybob
        last edited by

        @johnpoz:

        but you clearly stated your NOT natting on pfsense.

        but robertog said
        @robertog:

        i have just nat in modem, means i havent setup nat on pfsense.

        which could mean that because he hasn't done anything to setup NAT in pfSense he assumes pfSense is not NATing. But my recollection is that NAT is on by default in pfSense between LAN and WAN.

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        • johnpozJ
          johnpoz LAYER 8 Global Moderator
          last edited by

          Yup I agree nat is on by default normally.  but way I read it was he turned nat off.

          Why would he mention that he was not running it??  Unless he knew for sure it was on or off?

          @robertog can you verify for us if you turned NAT off?

          here
          http://doc.pfsense.org/index.php/Outbound_NAT

          To completely disable NAT and all firewall function from all interfaces, do the following. Note that you will skip the previous section ("Disable NAT") when taking this approach.

          Go to the System: Advanced page and click the Firewall / NAT tab.
              Check the box to "Disable Firewall / Disable all packet filtering."
              Save changes.

          To completely disable NAT to have a routing-only firewall, do the following.

          Go to the Firewall -> NAT page, and click the Outbound tab.
              Select the option "Manual Outbound NAT rule generation (Advanced Outbound NAT (AON))" and click Save.
              Remove all automatically generated NAT rules at the bottom of the screen.
              Apply changes
          –-

          Did you do either of those on your pfsense box?  If not then NAT would be on, and would explain why it works atleast some times - because if you had turned NAT off I don't see how it would work at all.

          So again I would suggest you remove the "modems" nat and allow pfsense to handle your nat/firewall/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 2.7.2, 24.11

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          • R
            robertog
            last edited by

            Hello!
            thanks for your reply but at moment I cant verify if Nat off..Im in business trip sorry, I repeat you I havent setup nat on pfsense so if this means defaults pfsense has nat i didnt know….
            But do u think that can create problems and sometimes internet connection is up and down?
            thanks roberto

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            • stephenw10S
              stephenw10 Netgate Administrator
              last edited by

              As the others said by default pfSense will NAT between WAN and LAN. You almost certainly have this enabled. This means you are double NATing but that doesn't usually cause a problem. I have run double NAT setups for testing purposes for months before and never once experienced any issue. However you should be aware that under specific circumstances it can be a problem.

              You need to determine where the failure is occurring and you will probably need to be doing that locally. We could speculate what might be happening but without testing it will only be speculation.  ;)

              The first thing I would look at is the pfSense logs. Look for WAN disconnects. Look at the RRD graphs of connection quality. Are there periods of packet loss or high latency?

              How is your WAN address assigned? Static IP?

              Steve

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              • R
                robertog
                last edited by

                hello,
                thanks for reply when i come back in office i will do of course.
                I have wan ip static.

                bye
                roberto

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                • johnpozJ
                  johnpoz LAYER 8 Global Moderator
                  last edited by

                  "Look at the RRD graphs of connection quality. Are there periods of packet loss or high latency?"

                  But that is really not testing his internet connection in the current setup because pfsense gateway is his modem.  His ISP could be offline and pfsense would still think internet is happy with a <1ms response time because he is just talking to the lan of his modem.

                  Which is why I suggest he puts pfsense on the border so that yes now he can see what the internet connection is doing.

                  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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                  • stephenw10S
                    stephenw10 Netgate Administrator
                    last edited by

                    @johnpoz:

                    But that is really not testing his internet connection in the current setup because pfsense gateway is his modem.

                    That's true. However if it does show something that will be a big clue.  ;)
                    The fact that the connection is solid when the pfSense box is removed suggests a problem on the local side of the modem.
                    Having a static WAN means that it's unlikely to show anything in the system logs except perhaps if it's a faulty cable.

                    Having a public IP on the pfSense WAN and a single NAT config is a better setup but that should not stop it working as it is.

                    Steve

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      I agree it can work with double nat, as stated before it is not ideal sort of setup.  But it should work - but he mentions

                      "Can pfsense talk to your "modem" – is the modem online - YES"

                      Well that tells me its his ISP or pfsense.  I would look to ISP first, but since his pfsense is not directly connected and behind a nat.  It is impossible to tell if pfsense can not talk to the gateway.  Which he would see instantly if pfsense was on public IP.

                      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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                      • stephenw10S
                        stephenw10 Netgate Administrator
                        last edited by

                        @johnpoz:

                        he mentions

                        "Can pfsense talk to your "modem" – is the modem online - YES"

                        Good point. Though that doesn't mean it's continuously online. However that should show up in the logs.

                        Much as I'm enjoying this speculating I think I'll wait for more information.  ;)

                        Steve

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                        • R
                          robertog
                          last edited by

                          hi,
                          thanks guys for sharing your ideas and suggestions. I can't wait when i am physically back in the office (cc. 24.9) in order to try suggested options & share back with you all results. Roberto

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