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    loopback address being blocked?

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

      And still not the commands I actually asked for.. Lets see the output of netstat or sockstat actually showing something bound to loopback.

      Sockstat prob better because would actually show "what" is bound to that port.

      Again - there is no firewall rule that could block pfsense from talking to itself.

      You could have some race condition where something else is binding to 443 on loopback?? The gui will try and bind to everything.. So maybe you have something trying to bound to 443, before the gui can bind to it on loopback? So lets see sockstat " grep :443 showing what process if anything is bound to the loopback on that port.

      An intelligent man is sometimes forced to be drunk to spend time with his fools
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      SG-4860 24.11 | Lab VMs 2.7.2, 24.11

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      • L
        ludejim
        last edited by

        My bad. I just saw your screen shot and thought that’s what you were referring to. Here is a sockstat | grep :443

        Image

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        • L
          ludejim
          last edited by

          @johnpoz Now that we know multiple things are bound to loopback, is there a command that could help me determine what those things are. I can see they are Nginx servers, but I don’t know what they are associated with.

          I do have OpenVPN and HAProxy running. My OpenVPN instance is using the default port of 1194. HAProxy is bound to port 80 for a web server.

          Unless those two items do something in the background I am unaware of, I’m not sure what the other items are that are binding to port 443 on the loopback.

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          • johnpozJ
            johnpoz LAYER 8 Global Moderator
            last edited by johnpoz

            nginx is the gui..

            Those are the pids of the processes, 2 workers and the main one.. on mine for example

            [2.4.5-RELEASE][admin@sg4860.local.lan]/root: ps -ax | grep 82772
            82772  -  Is        0:00.00 nginx: master process /usr/local/sbin/nginx -c /var/etc/nginx-webConfigurator.conf (nginx)
            38899  1  S+        0:00.00 grep 82772
            

            Again there is no firewall rule that would prevent access to itself.. Lets see the output of your curl with the -v so we can see exactly what is going on.

            [2.4.5-RELEASE][admin@sg4860.local.lan]/root: curl -v https://127.0.0.1:8443
            *   Trying 127.0.0.1:8443...
            * TCP_NODELAY set
            * Connected to 127.0.0.1 (127.0.0.1) port 8443 (#0)
            * ALPN, offering h2
            * ALPN, offering http/1.1
            * Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH
            * successfully set certificate verify locations:
            *   CAfile: /usr/local/share/certs/ca-root-nss.crt
              CApath: none
            * TLSv1.2 (OUT), TLS header, Certificate Status (22):
            * TLSv1.2 (OUT), TLS handshake, Client hello (1):
            * TLSv1.2 (IN), TLS handshake, Server hello (2):
            * TLSv1.2 (IN), TLS handshake, Certificate (11):
            * TLSv1.2 (OUT), TLS alert, unknown CA (560):
            * SSL certificate problem: self signed certificate in certificate chain
            * Closing connection 0
            curl: (60) SSL certificate problem: self signed certificate in certificate chain
            More details here: https://curl.haxx.se/docs/sslcerts.html
            

            Also sniff on the localhost while you try and do your test.. So you can actually see the connection attempt, and the source IP, etc..

            So here example you see me doing that above test while doing a packet capture on localhost for my port 8443

            sniff.png

            For grins check your loopback rules

            [2.4.5-RELEASE][admin@sg4860.local.lan]/root: pfctl -sr | grep loopback
            pass in on lo0 inet all flags S/SA keep state label "pass IPv4 loopback"
            pass out on lo0 inet all flags S/SA keep state label "pass IPv4 loopback"
            pass in on lo0 inet6 all flags S/SA keep state label "pass IPv6 loopback"
            pass out on lo0 inet6 all flags S/SA keep state label "pass IPv6 loopback"
            

            You do show your lo up and on 127.0.0.1? with an ifconfig

            lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
                    options=680003<RXCSUM,TXCSUM,LINKSTATE,RXCSUM_IPV6,TXCSUM_IPV6>
                    inet6 ::1 prefixlen 128
                    inet6 fe80::1%lo0 prefixlen 64 scopeid 0x7
                    inet 127.0.0.1 netmask 0xff000000
                    nd6 options=21<PERFORMNUD,AUTO_LINKLOCAL>
                    groups: lo
            

            Also so we are sure.. Is this baremetal or is pfsense on some VM?

            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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            • L
              ludejim
              last edited by

              curl command and response:
              curlCommand

              Packet capture during curl command captured nothing:
              PacketCaptureDuringCurlCommand

              loopback rules:
              loopbackRules

              ifconfig lo0 is up:
              lo0up

              Great question, my pfsense is being hosted on eSXI.

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              • johnpozJ
                johnpoz LAYER 8 Global Moderator
                last edited by

                do you have a route for loopback?

                example

                [2.4.5-RELEASE][admin@sg4860.local.lan]/root: netstat -rn | grep 127
                127.0.0.1          link#7             UH          lo0
                [2.4.5-RELEASE][admin@sg4860.local.lan]/root: 
                

                There is mine..

                That error in curl
                Immediate connect fail for 127.0.0.1: Can't assign requested address

                Can you ping localhost?

                [2.4.5-RELEASE][admin@sg4860.local.lan]/root: ping localhost
                PING localhost (127.0.0.1): 56 data bytes
                64 bytes from 127.0.0.1: icmp_seq=0 ttl=64 time=0.128 ms
                64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.063 ms
                

                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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                • L
                  ludejim
                  last edited by

                  I can’t ping localhost:
                  Cantping

                  Netstat results:
                  Netstat

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                  • kiokomanK
                    kiokoman LAYER 8
                    last edited by kiokoman

                    it's in the wrong interface
                    127.0.0.1 link#4 UH lo0

                    should be lo0, not vmx0
                    idk how you ended up with something like this 😂

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                    • johnpozJ
                      johnpoz LAYER 8 Global Moderator
                      last edited by

                      Yeah that is clearly Borked!!

                      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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                      • L
                        ludejim
                        last edited by ludejim

                        Borked it is! I can see how to assign all other interfaces. Anyway to reassign the loopback?

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          Never seen such a thing.. Some weirdness with interfaces being re-arranged when interfaces added in esxi maybe?

                          I don't know how you would re-assign that to be honest.

                          I would start over with new VM..

                          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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                          • L
                            ludejim
                            last edited by

                            That’s what I figured. I just backed up all my configurations and began setting up the new VM. It’ll have to wait for tonight because work from home and schooling from home. We need the internet for the day. I’ll let you guys know how it works out. Thanks for the help!

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                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              I would double check your lo0 assignment before you get to far into the config ;)

                              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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                              • L
                                ludejim
                                last edited by

                                Are you taking about on the new VM? If so, that was my going to be step one.

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                                • johnpozJ
                                  johnpoz LAYER 8 Global Moderator
                                  last edited by

                                  Yeah on the new vm ;)

                                  Do you have any other VMs running on this host that you could look to see how the lo0 is assigned?

                                  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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                                  • L
                                    ludejim
                                    last edited by

                                    I simply rebooted the pfsense VM and the loopback was reassigned to lo0. What a headache for apparently no reason!

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                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator
                                      last edited by

                                      I would of assumed you had done that already ;) When it wasn't working the first time?

                                      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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                                      • L
                                        ludejim
                                        last edited by

                                        Unfortunately no. I rarely if ever need to restart that VM. It’s uptime was 172 days prior to my restart.

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