Catching the "NULL" packets

[bapatsubodh]

In "show ip interface cache flow" command packets for which the destination interface is shown as "NULL" but still these packets are routed by the router to the destination address. Is there is any way to catch or to track these packets using access list or any other mechanism

Thanks and Advance

Subodh

[sivakondalarao]

1) but still these packets are routed by the router to the destination address ?----it will go to null interface and the packets are dropped

2) Is there is any way to catch ?------yes you can use a filter " show ip cache flow | inc Null " will give the packets which are destinated to Null interface