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    Intermittent connection issue

    Scheduled Pinned Locked Moved DHCP and DNS
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    • K
      kevindd992002
      last edited by kevindd992002

      Here's a traceroute that I sent them a few months ago: https://pastebin.com/JqPx326v

      That looks like the RTO starts from the hop that's within the ISP network. Is that enough evidence for them to conclude that the problem is in their network?

      And then 3 minutes after the issue, it got resolved and the traceroute results became like this: https://pastebin.com/XYbNMiWy

      Raffi_R 1 Reply Last reply Reply Quote 0
      • johnpozJ
        johnpoz LAYER 8 Global Moderator
        last edited by johnpoz

        You got to the end point in that trace.. That all hops along the way do not naswer does not always mean anything..

        Not sure what you think that shows as a problem?

        Tracing route to www.pfsense.org [208.123.73.69]
        over a maximum of 30 hops:
        
          1    <1 ms    <1 ms    <1 ms  192.168.9.253
          2    10 ms     9 ms    16 ms  50.4.132.1
          3    11 ms    17 ms    10 ms  76.73.191.106
          4     9 ms     9 ms     8 ms  76.73.164.142
          5    12 ms    10 ms     9 ms  76.73.164.154
          6    13 ms    10 ms    10 ms  76.73.191.242
          7    11 ms    21 ms    10 ms  143.59.95.224
          8    30 ms    15 ms    18 ms  75.76.35.8
          9     *       13 ms    11 ms  4.16.38.157
         10     *        *        *     Request timed out.
         11    36 ms    46 ms    37 ms  4.14.49.2
         12    41 ms    35 ms    35 ms  64.20.229.158
         13    36 ms    35 ms    35 ms  66.219.34.194
         14    34 ms    38 ms    35 ms  208.123.73.4
         15    39 ms    35 ms    39 ms  208.123.73.69
        

        So from that trace I guess I am having issues getting to www.pfsense.org?

        same goes for cnn seems

        $ tracert -d www.cnn.com
        
        Tracing route to turner-tls.map.fastly.net [151.101.185.67]
        over a maximum of 30 hops:
        
          1    <1 ms     3 ms    <1 ms  192.168.9.253
          2    10 ms    11 ms    16 ms  50.4.132.1
          3    19 ms    20 ms     8 ms  76.73.191.106
          4    11 ms    10 ms     9 ms  76.73.164.142
          5    13 ms    10 ms    11 ms  76.73.164.154
          6    10 ms    11 ms    11 ms  76.73.191.242
          7    10 ms    10 ms    10 ms  143.59.95.224
          8    13 ms     9 ms    10 ms  75.76.35.8
          9     *        *        *     Request timed out.
         10    12 ms    10 ms    10 ms  151.101.185.67
        

        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
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        K 1 Reply Last reply Reply Quote 0
        • K
          kevindd992002 @johnpoz
          last edited by

          @johnpoz said in Non-forwarding Resolver intermittent operation:

          You got to the end point in that trace.. That all hops along the way do not naswer does not always mean anything..

          Not sure what you think that shows as a problem?

          Tracing route to www.pfsense.org [208.123.73.69]
          over a maximum of 30 hops:
          
            1    <1 ms    <1 ms    <1 ms  192.168.9.253
            2    10 ms     9 ms    16 ms  50.4.132.1
            3    11 ms    17 ms    10 ms  76.73.191.106
            4     9 ms     9 ms     8 ms  76.73.164.142
            5    12 ms    10 ms     9 ms  76.73.164.154
            6    13 ms    10 ms    10 ms  76.73.191.242
            7    11 ms    21 ms    10 ms  143.59.95.224
            8    30 ms    15 ms    18 ms  75.76.35.8
            9     *       13 ms    11 ms  4.16.38.157
           10     *        *        *     Request timed out.
           11    36 ms    46 ms    37 ms  4.14.49.2
           12    41 ms    35 ms    35 ms  64.20.229.158
           13    36 ms    35 ms    35 ms  66.219.34.194
           14    34 ms    38 ms    35 ms  208.123.73.4
           15    39 ms    35 ms    39 ms  208.123.73.69
          

          So from that trace I guess I am having issues getting to www.pfsense.org?

          Of course not! Some routers are setup to not respond to ICMP requests, I know that.

          But how do you explain my first and second traceroute before and after (three minutes interval) the issue? Is it because the route to the same server changed in a span of 3 minutes?

          1 Reply Last reply Reply Quote 0
          • Raffi_R
            Raffi_ @kevindd992002
            last edited by

            @kevindd992002 said in Non-forwarding Resolver intermittent operation:

            Here's a traceroute that I sent them a few months ago: https://pastebin.com/JqPx326v

            That looks like the RTO starts from the hop that's within the ISP network. Is that enough evidence for them to conclude that the problem is in their network?

            And then 3 minutes after the issue, it got resolved and the traceroute results became like this: https://pastebin.com/XYbNMiWy

            @kevindd992002 That's not really proof of an issue on their network. Not all hops along the route will always respond. It's common to have hops that don't respond along the route. As long as at the end you get to the server, that's what matters. Also, the hops are not taking very long so that also looks OK.

            K 1 Reply Last reply Reply Quote 0
            • K
              kevindd992002 @Raffi_
              last edited by

              @Raffi_ said in Non-forwarding Resolver intermittent operation:

              @kevindd992002 said in Non-forwarding Resolver intermittent operation:

              Here's a traceroute that I sent them a few months ago: https://pastebin.com/JqPx326v

              That looks like the RTO starts from the hop that's within the ISP network. Is that enough evidence for them to conclude that the problem is in their network?

              And then 3 minutes after the issue, it got resolved and the traceroute results became like this: https://pastebin.com/XYbNMiWy

              @kevindd992002 That's not really proof of an issue on their network. Not all hops along the route will always respond. It's common to have hops that don't respond along the route. As long as at the end you get to the server, that's what matters. Also, the hops are not taking very long so that also looks OK.

              Right, that's what I thought. I just posted the screenshots here in case you guys see something out of the ordinary.

              1 Reply Last reply Reply Quote 0
              • Raffi_R
                Raffi_ @kevindd992002
                last edited by

                @kevindd992002 said in Non-forwarding Resolver intermittent operation:

                Yeah, I know how ISP's react when you say that. They panic and makes things solved faster. There are competitors, for sure, but in my condo there's only one offering FTTH connections, the one that I'm using now. The others are using crappy phone copper cables which are very substandard. And I just switched from that copper ISP to this fiber ISP since January 2019 so not long ago.

                Off topic, but we're actually in the copper test industry. Believe it or not, they have technology now that is able to get close to Gigabit speeds on those old copper lines if the ISP is willing to invest in it. I'm curious are you in Australia? Here in the US, the old phone lines have been mostly abandoned in terms of further investment.

                K 1 Reply Last reply Reply Quote 0
                • K
                  kevindd992002 @Raffi_
                  last edited by

                  @Raffi_ said in Non-forwarding Resolver intermittent operation:

                  @kevindd992002 said in Non-forwarding Resolver intermittent operation:

                  Yeah, I know how ISP's react when you say that. They panic and makes things solved faster. There are competitors, for sure, but in my condo there's only one offering FTTH connections, the one that I'm using now. The others are using crappy phone copper cables which are very substandard. And I just switched from that copper ISP to this fiber ISP since January 2019 so not long ago.

                  Off topic, but we're actually in the copper test industry. Believe it or not, they have technology now that is able to get close to Gigabit speeds on those old copper lines if the ISP is willing to invest in it. I'm curious are you in Australia? Here in the US, the old phone lines have been mostly abandoned in terms of further investment.

                  I can imagine. I was mostly talking about how sub-standard the copper wires are here in our condo. Even the copper ISP's themselves tell me that the copper wires that the contractors used in this condo are crap. The copper wires in the building's cabinet are worse than how spaghetti looks like. And no one wants to invest to replace those. I'm in the Philippines, so a third-world country, but Internet service here came a long way already. My two service plans are 35 down/35 up (around $31) and 300 down/300 up (around $87).

                  1 Reply Last reply Reply Quote 1
                  • K
                    kevindd992002
                    last edited by kevindd992002

                    @Raffi_

                    The Asus router as the main router and without pfsense has been issue-free for the last two days. It's still too early to tell but I'll continue monitoring during the weekend (the time when the issue usually occurs most) before I come to a conclusion. If it does run flawless until Monday though, I'm not sure how to continue troubleshooting pfsense except to uninstall and reinstall it from scratch. I mean that's an easy task when I just need to reload the config but if I am to go that route I would want to not carry over any settings from the config (which might be corrupted or something, for all we know).

                    Raffi_R 1 Reply Last reply Reply Quote 0
                    • Raffi_R
                      Raffi_
                      last edited by

                      @kevindd992002 Interesting. Ok, that sounds like a good plan. Yea give it a little while to see how it goes. We'll see what the next step is from there. Have a good weekend.
                      Raffi

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                      • K
                        kevindd992002
                        last edited by

                        @Raffi_

                        After 5 days of continuously using the ASUS router, I've never had any single occurrence of the issue! That isolates the ASUS router, cables, and ISP modem from being the root cause of the issue.

                        I've decided, just now, to switch to pfsense and as soon as I've plugged it in and waited for everything to go green in the Dashboard, I experienced the issue. It's got to be either the pfsense software itself or the physical hardware that hosts pfsense (although I doubt this). What can you recommend as a next step here?

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                        • johnpozJ
                          johnpoz LAYER 8 Global Moderator
                          last edited by

                          And your asus router was actual resolving for dns?

                          You title says non forwarding problems.. I find it unlikely that your asus router was resolving for dns vs forwarding..

                          Do you understand what the difference is?

                          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

                          K 1 Reply Last reply Reply Quote 0
                          • K
                            kevindd992002 @johnpoz
                            last edited by kevindd992002

                            @johnpoz said in Non-forwarding Resolver intermittent operation:

                            And your asus router was actual resolving for dns?

                            You title says non forwarding problems.. I find it unlikely that your asus router was resolving for dns vs forwarding..

                            Do you understand what the difference is?

                            Yes, I understand the difference between DNS resolver and DNS forwarder. I've already established this a few posts above. How can I rename the title for this whole thread and move it to the correct section? So that we can all be over the technicalities. Are my test results still not convincing for you that pfsense is causing my issue? What can I do to convince you?

                            The ASUS router is NOT a DNS resolver. It is a DNS forwarder and I was forwarding to the OpenDNS servers. That's the only main difference I see: pfsense was set as a DNS resolver (using root hints and not forwarding) while the ASUS router does not have this feature and is simply doing DNS forwarding.

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                            • johnpozJ
                              johnpoz LAYER 8 Global Moderator
                              last edited by

                              So then - troubleshoot your dns problem when your "resolving" Or set pfsense to forward to opendns like your asus was 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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                              • Raffi_R
                                Raffi_ @kevindd992002
                                last edited by

                                @kevindd992002 said in Non-forwarding Resolver intermittent operation:

                                How can I rename the title for this whole thread and move it to the correct section?

                                FYI, you can change the title of this topic by going up to your very first post, then click on the 3 dots and go to edit. Then above the text box where it shows the title, you can go in and edit it to help avoid any confusion. Maybe something more generic like intermittent connection issue or whatever you like. As for moving it to the correct section, that would have to be done by someone else. You can start a new topic in the correct section if you'd like, but I think we already made some progress here.

                                After 5 days of continuously using the ASUS router, I've never had any single occurrence of the issue! That isolates the ASUS router, cables, and ISP modem from being the root cause of the issue.

                                I've decided, just now, to switch to pfsense and as soon as I've plugged it in and waited for everything to go green in the Dashboard, I experienced the issue. It's got to be either the pfsense software itself or the physical hardware that hosts pfsense (although I doubt this). What can you recommend as a next step here?

                                Here is what I would suggest doing if you haven't already.

                                • Make a backup of your current pfSense config.
                                • Do a fresh install of the latest pfSense (2.4.4-RELEASE-p3).
                                • Configure your interfaces as needed.
                                • Do not install any additional packages.
                                • Leave all the default settings. pfSense is pretty darn secure out of the box, certainly more secure then the Asus anyway.

                                Then let's see where that gets you.

                                Raffi

                                K 1 Reply Last reply Reply Quote 0
                                • K
                                  kevindd992002 @Raffi_
                                  last edited by

                                  @johnpoz said in Non-forwarding Resolver intermittent operation:

                                  So then - troubleshoot your dns problem when your "resolving" Or set pfsense to forward to opendns like your asus was doing.

                                  I thought even you agreed that this is not a DNS problem? So why would I concentrate on troubleshooting DNS? I'm pinging an IP address when the issue happens so that in itself tells everyone already that it isn't a DNS issue.

                                  @Raffi_ said in Non-forwarding Resolver intermittent operation:

                                  @kevindd992002 said in Non-forwarding Resolver intermittent operation:

                                  How can I rename the title for this whole thread and move it to the correct section?

                                  FYI, you can change the title of this topic by going up to your very first post, then click on the 3 dots and go to edit. Then above the text box where it shows the title, you can go in and edit it to help avoid any confusion. Maybe something more generic like intermittent connection issue or whatever you like. As for moving it to the correct section, that would have to be done by someone else. You can start a new topic in the correct section if you'd like, but I think we already made some progress here.

                                  After 5 days of continuously using the ASUS router, I've never had any single occurrence of the issue! That isolates the ASUS router, cables, and ISP modem from being the root cause of the issue.

                                  I've decided, just now, to switch to pfsense and as soon as I've plugged it in and waited for everything to go green in the Dashboard, I experienced the issue. It's got to be either the pfsense software itself or the physical hardware that hosts pfsense (although I doubt this). What can you recommend as a next step here?

                                  Here is what I would suggest doing if you haven't already.

                                  • Make a backup of your current pfSense config.
                                  • Do a fresh install of the latest pfSense (2.4.4-RELEASE-p3).
                                  • Configure your interfaces as needed.
                                  • Do not install any additional packages.
                                  • Leave all the default settings. pfSense is pretty darn secure out of the box, certainly more secure then the Asus anyway.

                                  Then let's see where that gets you.

                                  Raffi

                                  Changed the title already, thanks.

                                  I was afraid that the only step I'm left with is to reinstall. But yeah, I can do that, but I'll probably not be able to until next week because I don't have a serial-to-USB adapter with me right now. I'll report back when I'm done with this but I'll continue monitoring while using the current pfsense installation.

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                                  • K
                                    kevindd992002
                                    last edited by kevindd992002

                                    @Raffi_ , since I didn't have time to start pfsense from scratch yet, I decided to just reset to factory defaults and restore the config. Same thing still happens.

                                    One semi-consistent thing that I observed though is that the issue happens when I turn on my desktop computer from a state where it is turned off for a couple of hours. I say "semi-consistent" because when I restart or shut it down now and turn it back on immediately, the issue cannot be recreated. I've been observing this for a couple of days and it's as if that it is the one bogging down the whole network. Then I wait for 5 to 10 minutes and things come back to normal.

                                    There's no special network configuration with my desktop computer aside from these things:

                                    1. Uses NUT (Network UPS Tools) to connect to the UPS master connected to pfsense.
                                    2. Wireshark/NPCap is installed but not running (the Npcap Loopback Adapter is installed)
                                    3. Hyper-V Manager is installed and the default virtual switch (has its own internal subnet) is configured.
                                    4. A mapped drive connecting to the Synology NAS on the other end of the OpenVPN tunnel is configured.

                                    Can you think of anything out of those that could cause this?

                                    Could it perhaps be a broadcast storm caused by the desktop PC? If so, how can I confirm this?

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                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator
                                      last edited by

                                      @kevindd992002 said in Intermittent connection issue:

                                      how can I confirm this?

                                      Sniff and see - be it on any device on that same L2 or pfsense... If you want to know what is going on - just look.

                                      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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                                      • Raffi_R
                                        Raffi_
                                        last edited by

                                        I agree with what John said. If you suspect something like the desktop traffic being an issue, run a packet capture on pfsense using the LAN interface.

                                        I would suggest starting a packet capture on pfsense LAN before you turn on that PC which is causing the issues. Then while the capture is running, turn on the PC (after it's been off long enough to cause trouble) and see what's happening. Take note of the time when you first connect the PC so you can figure out at what point in the capture the PC was connected. I think it's a little coincidental that the default DHCP lease time in pfsense is 2 hours and the time it takes for your PC to stay disconnected before it starts causing trouble matches up with that.

                                        Have you tried manually configuring a fixed IP on that PC instead of requesting a DHCP lease?

                                        Raffi

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                                        • K
                                          kevindd992002 @Raffi_
                                          last edited by

                                          @Raffi_ said in Intermittent connection issue:

                                          I agree with what John said. If you suspect something like the desktop traffic being an issue, run a packet capture on pfsense using the LAN interface.

                                          I would suggest starting a packet capture on pfsense LAN before you turn on that PC which is causing the issues. Then while the capture is running, turn on the PC (after it's been off long enough to cause trouble) and see what's happening. Take note of the time when you first connect the PC so you can figure out at what point in the capture the PC was connected. I think it's a little coincidental that the default DHCP lease time in pfsense is 2 hours and the time it takes for your PC to stay disconnected before it starts causing trouble matches up with that.

                                          Have you tried manually configuring a fixed IP on that PC instead of requesting a DHCP lease?

                                          Raffi

                                          Ok, I'll try that and report back.

                                          No, I have not tried a static IP on the PC but it has an IP reservation from the DHCP server, like all my other servers/PC's that I need to RDP from outside do. But yeah, I'll see if a static IP makes a difference to rule out DHCP.

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                                          • johnpozJ
                                            johnpoz LAYER 8 Global Moderator
                                            last edited by johnpoz

                                            Keep in mind that default packet capture on pfsense is set to 100, so you will most likely want to adjust that.. 0 would be a good setting.. Just don't forget its running ;)

                                            defaultcapture.jpg

                                            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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