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    How to detect a cyber attack

    Scheduled Pinned Locked Moved General pfSense Questions
    28 Posts 9 Posters 4.0k Views
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    • DerelictD
      Derelict LAYER 8 Netgate
      last edited by

      It depends. Sometimes you want to know that the WAN can actually reach the internet, not just the ISP gateway.

      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)

      hugoeyngH 1 Reply Last reply Reply Quote 1
      • hugoeyngH
        hugoeyng @Derelict
        last edited by

        @Derelict Instead Google DNS or ISP DNS what IP could I use to monitor? Any suggestion?

        I love pfSense!

        Hugo Eyng
        Datamais Sistemas

        1 Reply Last reply Reply Quote 0
        • KOMK
          KOM
          last edited by

          Perhaps one of your ISPs core routers. Do a traceroute somewhere and see what the second or third hop is.

          hugoeyngH 1 Reply Last reply Reply Quote 1
          • stephenw10S
            stephenw10 Netgate Administrator
            last edited by

            I've never seen an issue using 8.8.8.8 personally.

            The fact that you have some SWAP usage shown in that screenshot shows that at some point you exhausted the RAM. That can make things go waaaay slower.
            Check the Status > Monitoring graphs for memory usage. Does it peak when you see these incidents?

            Steve

            RicoR 1 Reply Last reply Reply Quote 1
            • RicoR
              Rico LAYER 8 Rebel Alliance @stephenw10
              last edited by

              @stephenw10 said in How to detect a cyber attack:

              I've never seen an issue using 8.8.8.8 personally.

              Yeah I like to use 8.8.8.8, 8.8.4.4 and 1.1.1.1 for monitoring too.

              -Rico

              hugoeyngH 1 Reply Last reply Reply Quote 1
              • hugoeyngH
                hugoeyng @KOM
                last edited by

                @KOM Great!

                I love pfSense!

                Hugo Eyng
                Datamais Sistemas

                1 Reply Last reply Reply Quote 0
                • hugoeyngH
                  hugoeyng @Rico
                  last edited by

                  @Rico I am not sure but is possible that "You will get false positives using Google's DNS servers." as said @tim-mcmanus.

                  But I liked @KOM suggestion.

                  I love pfSense!

                  Hugo Eyng
                  Datamais Sistemas

                  1 Reply Last reply Reply Quote 0
                  • RicoR
                    Rico LAYER 8 Rebel Alliance
                    last edited by

                    I never heard of Google deliberately dropping ICMP traffic to their DNS Servers and personally I never had any issues with it.

                    WANGW.png
                    WANGW is using 8.8.8.8 atm.

                    -Rico

                    1 Reply Last reply Reply Quote 2
                    • RicoR
                      Rico LAYER 8 Rebel Alliance
                      last edited by

                      Monitoring any ISP router does not really show a reliable route to the Internet.
                      Your ISP could have any routing/peering issue, even if their (core) router is perfectly reachable from your side.

                      -Rico

                      1 Reply Last reply Reply Quote 2
                      • KOMK
                        KOM
                        last edited by

                        It shows you if there is a problem between you and your ISP. Anything past that is out of your control. The whole point of the thing is to be a gateway monitor, not a 5-hops-away monitor. The farther away you monitor, the more likely you will get a false positive of some sort, and I wouldn't want my gateway going down because there is a routing problem many hops away from me.

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

                          On the monitor IP topic, I agree with @Rico and @stephenw10. I have not had issue so far with google DNS. In fact I switched to Google DNS because I suddenly had issues with my ISP's (third hop router). After months of working fine, we had power failures in the area which I suspect also caused issues with that route on the ISP's network. My gateway was marked as down when it wasn't. Switched to 8.8.8.8 and it's been good since then. Is it a perfect solution? No. Will this happen to you? Probably not, but using a device IP on a specific route on the ISP's network to me seems like trouble. If that route goes down like in my case, the traffic will get rerouted and still reach where it needs to go on the web. But that can't happen if my gateway is marked as down and monitoring action is enabled. Ideally, I would like to be able to put in multiple monitor IPs, so if one is not responding another one could.

                          1 Reply Last reply Reply Quote 1
                          • stephenw10S
                            stephenw10 Netgate Administrator
                            last edited by

                            I will say that whilst I've never seen an issue with it on numerous pfSense installs, including my own, Google respond to ping there more as a courtesy. They could just stop responding. Also when you ping 8.8.8.8 you are hitting a machine via anycast so the service may vary depending on where you are pinging from.

                            Steve

                            Raffi_R 1 Reply Last reply Reply Quote 2
                            • Raffi_R
                              Raffi_ @stephenw10
                              last edited by

                              @stephenw10 said in How to detect a cyber attack:

                              I will say that whilst I've never seen an issue with it on numerous pfSense installs, including my own, Google respond to ping there more as a courtesy. They could just stop responding. Also when you ping 8.8.8.8 you are hitting a machine via anycast so the service may vary depending on where you are pinging from.

                              Steve

                              Let's hope they don't pull the rug out from under us. I think a lot of gateways would be marked as down :)

                              hugoeyngH 1 Reply Last reply Reply Quote 1
                              • hugoeyngH
                                hugoeyng @Raffi_
                                last edited by

                                @Raffi_ said in How to detect a cyber attack:

                                Let's hope they don't pull the rug out from under us. I think a lot of gateways would be marked as down

                                I hope so too!

                                I tried monitoring White House and Pentagon IP´s but it did not succedd.

                                Those IP´s, I believe, would be the last to be down. :)

                                Thank you everybody.

                                I love pfSense!

                                Hugo Eyng
                                Datamais Sistemas

                                Raffi_R A 2 Replies Last reply Reply Quote 1
                                • Raffi_R
                                  Raffi_ @hugoeyng
                                  last edited by

                                  @hugoeyng said in How to detect a cyber attack:

                                  @Raffi_ said in How to detect a cyber attack:

                                  Let's hope they don't pull the rug out from under us. I think a lot of gateways would be marked as down

                                  I hope so too!

                                  I tried monitoring White House and Pentagon IP´s but it did not succedd.

                                  Those IP´s, I believe, would be the last to be down. :)

                                  Thank you everybody.

                                  haha I hope you don't get a knock on the door from people in black suits.

                                  hugoeyngH 1 Reply Last reply Reply Quote 1
                                  • A
                                    akuma1x @hugoeyng
                                    last edited by

                                    @hugoeyng said in How to detect a cyber attack:

                                    I tried monitoring White House and Pentagon IP´s but it did not succedd.

                                    So, White House Down?

                                    https://www.imdb.com/title/tt2334879/

                                    ☺

                                    Jeff

                                    hugoeyngH 1 Reply Last reply Reply Quote 1
                                    • hugoeyngH
                                      hugoeyng @Raffi_
                                      last edited by

                                      @Raffi_ :))))))

                                      I love pfSense!

                                      Hugo Eyng
                                      Datamais Sistemas

                                      1 Reply Last reply Reply Quote 0
                                      • hugoeyngH
                                        hugoeyng @akuma1x
                                        last edited by

                                        @akuma1x hahaha The first to be under attack. Is not a good idea use it to monitoring. Is more secure using the butcher shop next door IP.

                                        I love pfSense!

                                        Hugo Eyng
                                        Datamais Sistemas

                                        1 Reply Last reply Reply Quote 1
                                        • R
                                          runningboy
                                          last edited by runningboy

                                          In most cases, a cyberattack is almost impossible to notice. This operation takes place instantly and the user does not even understand how the intruders entered the system and control it. This situation happened in the office where I work a few months ago. Cybercriminals tried to get hold of our customer base and spread this information online. They penetrated the network and got all the access codes and passwords from our system, which is why the programs crashed and, by chance, they were unable to commit theft. Since then, we've turned to Cyber ​​Essentials to help protect and support our system from potential threats. I hope this will not happen again.

                                          1 Reply Last reply Reply Quote 1
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