Hello Sanjoy,
here is the output of the command lookup tool
http://tools.cisco.com/Support/CLILookup/cltSearchAction.do?Application_ID=CLT&IndexId=IOS&IndexOptionId=123&SearchPhrase=%22*%22&Paging=25&ActionType=getCommandList&Bookmark=True
Usage Guidelines
A line card might drop packets because of encapsulation failure, absence of route information, or absence of adjacency information.
A packet is sent to a different switching path (punted) because Cisco Express Forwarding does not support the encapsulation or feature, the packet is destined for the router, or the packet has IP options, such as time stamp and record route. IP options are process switched.
Note If Cisco Express Forwarding IPv6 or dCEFv6 is enabled globally on the router, the show cef drop command displays IPv6 Cisco Express Forwarding counter information and IPv4 Cisco Express Forwarding counter information. If CEFv6 or dCEFv6 is not enabled globally on the router, the command displays only IPv4 Cisco Express Forwarding counter information.
Examples
The following is sample output from the show cef drop command:
Router# show cef drop
CEF Drop Statistics
Slot Encap_fail Unresolved Unsupported No_route No_adj ChksumErr
RP 4 89 0 4 0 0
1 0 0 0 0 0 0
2 0 0 5 0 0 5
IPv6 CEF Drop Statistics
Slot Encap_fail Unresolved Unsupported No_route No_adj
RP 2 33 0 2 0
1 0 0 3 0 0
2 0 0 0 0 0
Table 10 describes the significant fields shown in the display.
Table 10 show cef drop Field Descriptions
Field
Description
Slot
The slot number on which the packets were received.
Encap_fail
Indicates the number of packets dropped after exceeding the limit for packets punted to the processor due to missing adjacency information (Cisco Express Forwarding throttles packets passed up to the process level at a rate of one packet every two seconds).
Unresolved
Indicates the number of packets dropped due to an unresolved prefix in the Forwarding Information Base (FIB) table.
Unsupported
Indicates the number of packets fast-dropped by Cisco Express Forwarding (drop adjacency).
No_route
Indicates the number of packets dropped due to a missing prefix in the FIB table.
No_adj
Indicates the number of packets dropped due to incomplete adjacency.
ChksumErr
Indicates the number of IPv4 packets received with a checksum error.
Note This field is not supported for IPv6 packets.
In your case there is a great number of encap-fail and no route see descriptions above.
If in a MPLS scenario verify if the router is receveing traffic with an unexpected label.
Hope to help
Giuseppe
