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    IPSec is very slow between two pfsense routers

    Scheduled Pinned Locked Moved IPsec
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    • keyserK
      keyser Rebel Alliance @kevingoos
      last edited by keyser

      @kevingoos In principle it’s not your VPN settings. Those are technically fine.

      However: You will run into an issue with a stalling IPsec tunnel with those settings. There is an issue using AES-CGM right now - at least om ARM based boxes that stalls the tunnels. I have had precursors of VERY low throughput in GCM based tunnels before they stalled completely. So there is a small chance that you are hitting this. Try changing the Phase 1 + 2 Ciphers to AES-CBC (Listed as AES in the UI) and see if that helps.

      If not, you are likely seeing a packet fragmentation penalty and need to limit your MTU on the VPN tunnel.

      https://www.reddit.com/r/PFSENSE/comments/qzpm7k/having_weird_ipsec_issues_try_mss_clamping/

      Love the no fuss of using the official appliances :-)

      K 1 Reply Last reply Reply Quote 0
      • K
        kevingoos @keyser
        last edited by

        @keyser So I changed the P1 AES(256)
        And also changed my encryption on my 7100 to QAT:
        d66dcebe-be86-410d-8c2c-f88590cdb33b-image.png

        Now I get around 500 KB/s copying a file which is already a bit better but still not great.

        I will try lowering the encryption to 128 and see if that makes it acceptable

        keyserK 1 Reply Last reply Reply Quote 0
        • keyserK
          keyser Rebel Alliance @kevingoos
          last edited by

          @kevingoos said in IPSec is very slow between two pfsense routers:

          @keyser So I changed the P1 AES(256)
          And also changed my encryption on my 7100 to QAT:
          d66dcebe-be86-410d-8c2c-f88590cdb33b-image.png

          Now I get around 500 KB/s copying a file which is already a bit better but still not great.

          I will try lowering the encryption to 128 and see if that makes it acceptable

          remember to change the encryption on Phase 2 - that is where all that actual data gets encrypted - and thus where a performance difference really shows.

          Love the no fuss of using the official appliances :-)

          K 1 Reply Last reply Reply Quote 0
          • K
            kevingoos @keyser
            last edited by

            @keyser Ok should I also put Phase 2 on AES-CBC?

            keyserK 2 Replies Last reply Reply Quote 0
            • keyserK
              keyser Rebel Alliance @kevingoos
              last edited by

              @kevingoos Yes - i see the “2” i thought i wrote in the initial post after the “+” did in fact not register….

              Love the no fuss of using the official appliances :-)

              1 Reply Last reply Reply Quote 0
              • keyserK
                keyser Rebel Alliance @kevingoos
                last edited by keyser

                @kevingoos One other thing: When you change the phase 2 ciphers til CBC, you need to set SHA-256 as the Auth mechanism. It’s only when using GCM that you do not need a auth mechanism in P2.
                You should set your phase 1 transform to sha-256 while you are at it as well :-)

                Edit: in the UI it’s the HASH selection field in P1 and P2 i’m reffering to.

                Love the no fuss of using the official appliances :-)

                K 1 Reply Last reply Reply Quote 0
                • K
                  kevingoos @keyser
                  last edited by kevingoos

                  @keyser Ok now we have 585 KB/s copying a file through SMB. Not yet great but again a bit better...

                  This is what I have now on the 7100 side
                  a30f214a-9dc0-4b26-b601-5001021117d0-image.png

                  And this on the 2100 side
                  604b9c77-7c6d-4b4c-9684-0ab0728a9052-image.png

                  keyserK 1 Reply Last reply Reply Quote 0
                  • keyserK
                    keyser Rebel Alliance @kevingoos
                    last edited by

                    @kevingoos Yeah, those are solid settings to avoid the stalling IPSec tunnel. But since your speed is far from the “close to 30mbit” possible in your setup, we have to look elsewhere.

                    1.st off: SMB is crap over a line with latency - which is the case here.

                    So before we continue suspecting the VPN, please do a couple of tests:

                    1: install the iperf package on both your pfsenses.
                    2: Open iperf port 5201 TCP/UDP on “serverside” pfsense’ WAN interface from the public IP on your other pfsense.
                    3: Run some iperf tests from client pfsense to server pfsense.

                    This will tell us what we can actually expect between the two boxes when no VPN is involved.

                    After that run iperf on your SMB server and client and run the test againg between those two. Now we have an idea if the VPN severely limits throughput compared to RAW (non-VPN).

                    My guess is SMB is the culprit here…..

                    Love the no fuss of using the official appliances :-)

                    1 Reply Last reply Reply Quote 1
                    • Cool_CoronaC
                      Cool_Corona
                      last edited by

                      SMB is useless over VPN. Incredibly slow....

                      Cannot even stream FullHD video without lagging.

                      K 1 Reply Last reply Reply Quote 0
                      • N
                        NOCling
                        last edited by

                        User Intel Quick Assist on 71er Site and SafeXcel on the ARM Site.
                        User a good DH Group like 19, 20, 21.
                        Use wan optimized Stuff to push Data over VPN, not SMB, it designed is lan ony.

                        I run my NAS Backups over the Tunnel, with the Upload limiting around about 50MBit/s.
                        This Speed is no problem for the 21er, System Load 8-9%, Interrupt 18%.

                        And yes, if you use AES GCM with SafeXcel on ARM, you got stuck after som Time with the entire IPsec Stack.

                        Netgate 6100 & Netgate 2100

                        1 Reply Last reply Reply Quote 0
                        • K
                          kevingoos @Cool_Corona
                          last edited by

                          @cool_corona Yes I tested with SMB, but also Plex cannot stream any video over the IPSEC tunnel without buffering every 2 min

                          Cool_CoronaC keyserK 2 Replies Last reply Reply Quote 0
                          • Cool_CoronaC
                            Cool_Corona @kevingoos
                            last edited by

                            @kevingoos And the funny part is, hardware doesnt matter. No matter how much power the FW has, it doesnt matter.

                            Its much better on a 2.2.6 version of Pfsense. Then it works quickly and no issues.

                            Food for thought.

                            1 Reply Last reply Reply Quote 0
                            • keyserK
                              keyser Rebel Alliance @kevingoos
                              last edited by

                              @kevingoos Have you tried the iPerf tests I suggested?
                              Until you do, we cannot really say what is what - we need to see if the tunnel can carry the “up to 30mbit” possible in your scenario.

                              After that test - if no throughput is possible with iPerf either, look into limiting the fragmentation size as i suggested by using MSS Clamping on the tunnel. I don’t think that is you issue though, so…

                              My guess is your tunnel is fine when you do a 3 or 4 streams iPerf test (will pass about 30 mbit).
                              The issue is very likely the asyncronous speeds in both ends combined with the latency introduced. That’s a real throughput killer. It can very quickly completely kill single stream interactive protocols like SMB.

                              Love the no fuss of using the official appliances :-)

                              K 1 Reply Last reply Reply Quote 0
                              • K
                                kevingoos @keyser
                                last edited by kevingoos

                                @keyser Sorry currently I broke the VPN by updating 7100 to the latest version. But the update for the 2100 is not yet ready...
                                I will get back the moment I get this updated.

                                1 Reply Last reply Reply Quote 0
                                • K
                                  kevingoos
                                  last edited by

                                  So in the end I took some time off for this problem and today I switched to wireguard site to site.

                                  And now I am very happy with the performance (this is with SMB so not yet the full potential)
                                  2a8c178b-ecf9-4a15-ae80-8d4723b5a230-image.png

                                  So for me this probem is solved

                                  1 Reply Last reply Reply Quote 0
                                  • N
                                    NOCling
                                    last edited by

                                    The ARM GCM Problem is gone. It was in 22.05 and after 23.01 GCM runs again.

                                    I run my S2S with AES GCM 128, SHA256, DH19, and Upstream is the Iimit.
                                    In Run my NAS Backup over it and if the Docis 3.1 Modem is stable, it run over Days with max Upsteam Speed.

                                    Netgate 6100 & Netgate 2100

                                    1 Reply Last reply Reply Quote 1
                                    • P
                                      patrick.pesegodinski
                                      last edited by

                                      Hello.

                                      I have two Pfsense 2.6.0 configured with IPSEC, AES-NI on the hardware. The latency between the two links is 3ms.
                                      With IPSEC, the transfer does not exceed 5MB/s, whereas with OpenVPN, the transfer reaches 50MB/s, which is the maximum bandwidth of the internet link.

                                      I have already tested all protocols in phase 1 and 2 and the rate does not change.

                                      What could be "blocking" IPSEC?

                                      M 1 Reply Last reply Reply Quote 0
                                      • M
                                        michmoor LAYER 8 Rebel Alliance @patrick.pesegodinski
                                        last edited by

                                        @patrick-pesegodinski Could be fragmentation. Try setting MSS to 1350 or 1300 to start and test.
                                        How are you performing the speedtest? On a client behind the pfsense?
                                        Also please post the specs of your system

                                        Firewall: NetGate,Palo Alto-VM,Juniper SRX
                                        Routing: Juniper, Arista, Cisco
                                        Switching: Juniper, Arista, Cisco
                                        Wireless: Unifi, Aruba IAP
                                        JNCIP,CCNP Enterprise

                                        P 1 Reply Last reply Reply Quote 0
                                        • P
                                          patrick.pesegodinski @michmoor
                                          last edited by

                                          @michmoor

                                          The test is carried out by transferring files from the server at one end to computers at the other end.

                                          Should I reduce the MSS at both ends?

                                          Main Pfsense Configuration:

                                          Intel(R) Core(TM) i5-8400 CPU @ 2.80GHz
                                          Current: 2800MHz, Max: 2801MHz
                                          6 CPUs: 1 package(s) x 6 core(s)
                                          AES-NI CPU Crypto: Yes (active)
                                          QAT Crypto: No

                                          Secondary Pfsense Configuration:

                                          Intel(R) Core(TM) i3-8100 CPU @ 3.60GHz
                                          4 CPUs: 1 package(s) x 4 core(s)
                                          AES-NI CPU Crypto: Yes (active)
                                          QAT Crypto: No

                                          M 1 Reply Last reply Reply Quote 0
                                          • M
                                            michmoor LAYER 8 Rebel Alliance @patrick.pesegodinski
                                            last edited by

                                            @patrick-pesegodinski
                                            What NICs are used?
                                            Try reducing MSS on both.
                                            Are these SMB file transfers?

                                            Firewall: NetGate,Palo Alto-VM,Juniper SRX
                                            Routing: Juniper, Arista, Cisco
                                            Switching: Juniper, Arista, Cisco
                                            Wireless: Unifi, Aruba IAP
                                            JNCIP,CCNP Enterprise

                                            P 1 Reply Last reply Reply Quote 0
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