fp_netfilter_pre_routing and net_ratelimit Kernel Errors

[ServicePros]

Hey Everyone,

Newer to the RV340, but I've been trying to track down a internet connectivity issue. I keep seeing the following in the event logs. Any ideas? Thanks!

2020-Nov-20, 13:42:34 EST
warning
kern
kernel: [ 2351.651681] fp_netfilter_pre_routing: 10 callbacks suppressed
2020-Nov-20, 13:42:28 EST
warning
kern
kernel: [ 2345.916506] fp_netfilter_pre_routing: 42 callbacks suppressed
2020-Nov-20, 13:42:26 EST
warning
kern
kernel: [ 2343.660080] net_ratelimit: 6 callbacks suppressed
2020-Nov-20, 13:42:23 EST
warning
kern
kernel: [ 2340.655677] fp_netfilter_pre_routing: 18 callbacks suppressed
2020-Nov-20, 13:41:52 EST
warning
kern
kernel: [ 2309.837910] fp_netfilter_pre_routing: 12 callbacks suppressed
2020-Nov-20, 13:41:31 EST
warning
kern
kernel: [ 2289.345937] fp_netfilter_pre_routing: 14 callbacks suppressed
2020-Nov-20, 13:40:26 EST
warning
kern
kernel: [ 2224.176865] fp_netfilter_pre_routing: 2 callbacks suppressed
2020-Nov-20, 13:39:25 EST
warning
kern
kernel: [ 2163.094997] fp_netfilter_pre_routing: 16 callbacks suppressed
2020-Nov-20, 13:39:10 EST
warning
kern
kernel: [ 2147.882400] fp_netfilter_pre_routing: 2 callbacks suppressed
2020-Nov-20, 13:38:45 EST
warning
kern
kernel: [ 2122.656127] net_ratelimit: 4 callbacks suppressed
2020-Nov-20, 13:38:44 EST
warning
kern
kernel: [ 2121.906400] fp_netfilter_pre_routing: 40 callbacks suppressed
2020-Nov-20, 13:37:32 EST
warning
kern
kernel: [ 2049.686272] fp_netfilter_pre_routing: 14 callbacks suppressed
2020-Nov-20, 13:37:04 EST
warning
kern
kernel: [ 2021.703825] net_ratelimit: 7 callbacks suppressed

[marce1000]

                         - Not sure about the cause , but make sure to use the latest firmware available.

 M.

[ServicePros]

Yeah the device is on the latest firmware. I'm newer to the Cisco platform and my issue that I'm having a hard time finding explanations for the event log errors. I wish they included more information. Are there any online resources that you know of to help? The device is only a few months old, is it still under support?

Thanks, Jim 

[marce1000]

  - The error may relate to heavy or high traffic , as an example link below denotes. If possible try to monitor traffic volumes, that the device has to handle.

                                            https://bst.cloudapps.cisco.com/bugsearch/bug/CSCvg29701/?rfs=iqvred

  M.

[ServicePros]

That's odd because there was nobody there during this time. Could this be
causing internet connectivity issues and what should I do? Should should I
limit download bandwidth or something to that nature? I guess what I'm
asking is this causing a problem? Thank you

[marce1000]

                          - If no-user/app problems are seen, then the error could be bogus (bug) and considered unimportant.

 M.

[ServicePros]

kernel: [719422.165430] FIREWALL SYN-FLOOD:IN=eth2 OUT= DST_MAC=3c:57:31:84:a8:f5 SRC_MAC=:4a:1d:70:d0:81:41 SRC=87.251.70.79 DST=96.94.47.181 LEN=40 TOS=0x00 PREC=0x20 TTL=226 ID=123 PROTO=TCP SPT=65532 DPT=5746 WINDOW=1024 RES=0x00 SYN URGP=0 MARK=0xff00

2020-Nov-19, 18:07:20 GMT
warning
kern
kernel: [675940.536152] fp_netfilter_pre_routing: 42 callbacks suppressed

[marce1000]

 - The device seems to be under syn-flood attacks ; here are some links on how to mitigate with them :

          https://community.cisco.com/t5/security-documents/how-to-prevent-an-outbound-tcp-syn-flood-attack-on-the-edge/ta-p/3115686

         https://community.cisco.com/t5/security-documents/how-to-configure-the-router-to-minimize-a-denial-of-service-dos/ta-p/3117624

 M.

[natcomms]

you can't do that on RV series routers

[natcomms]

Has anyone found a solution? It happens 1-2 times every week. This is a huge problem for my customer when they're trying to make CC transactions for book appointments.  I'm very close to replacing the RV340 with something else. 

[yagnesh]

kernel: [ 5094.150150] fp_netfilter_pre_routing: 8 callbacks suppressed

I try to everything but this error not gone, i try to update latest firmware, try to reset router, upgrade my ISP 1gbps and many more...till error is again and again...

Please let me know if you find solution....