Deny UDP reverse path check block but other traffic permitted.

[mattgreaves]

Hi,

Hope someone can help me. We are seeing the following on our logs on the ASA and don't understand why some traffic is blocked due to RPF but then other traffic is permitted:

1    Oct 10 2014    11:01:19    106021    192.168.0.223        10.10.10.54        Deny UDP reverse path check from 192.168.0.223 to 10.10.10.54 on interface INSIDE

1    Oct 10 2014    11:00:19    106021    192.168.0.223        10.10.10.54        Deny UDP reverse path check from 192.168.0.223 to 10.10.10.54 on interface INSIDE

6    Oct 10 2014    11:00:12    302021    192.168.0.223    63510    10.10.10.54    0    Teardown ICMP connection for faddr 192.168.0.223/63510 gaddr 10.10.10.54/0 laddr 10.10.10.54/0

6    Oct 10 2014    11:00:03    302020    192.168.0.223    63510    10.10.10.54    0    Built inbound ICMP connection for faddr 192.168.0.223/63510 gaddr 10.10.10.54/0 laddr 10.10.10.54/0

1    Oct 10 2014    10:59:19    106021    192.168.0.223        10.10.10.54        Deny UDP reverse path check from 192.168.0.223 to 10.10.10.54 on interface INSIDE

1    Oct 10 2014    10:59:19    106021    192.168.0.223        10.10.10.54        Deny UDP reverse path check from 192.168.0.223 to 10.10.10.54 on interface INSIDE

Routes all exist in the right places or the permitted flows would fail.

Any help would be greatly appreciated.

Cheers,

Matt

[Vibhor Amrodia]

Hi,

Can you share the configuration ?

Thanks and Regards,

Vibhor Amrodia

[mattgreaves]

Hi Vibhor,

Unfortunately I am unable to share the config from the devices due to their nature. If you could point me in a direction to investigate that would be appreciated.

Thanks and sorry,

Matt