[c-nsp] ASR9k - input drops

[Jason Lixfeld]

On 2011-02-15, at 8:41 PM, Pshem Kowalczyk wrote:

> We're trying to determine a cause of 'total input drops' on one of
> TenG interfaces on ASR9k. The interface is a CE facing one.
> (statistics have not been cleared, but the issue is ongoing):

I actually just closed off a TAC case to determine a similar issue.  

In addition to your show commands, you can see what drops the network processor on the card is seeing relative to the interface counters:

1.  Find out what network processor is controlling the particular interface on the linecard in question.  ie, for Gi0/0/0/0:

RP/0/RSP0/CPU0:bfr01.60hudson01#show controllers np ports all location 0/0/CPU0 
Wed Feb 16 00:56:34.424 EST

                Node: 0/0/CPU0:
----------------------------------------------------------------

NP Bridge Fia                       Ports                      
-- ------ --- --------------------------------------------------- 
0  0      0   GigabitEthernet0/0/0/10 - GigabitEthernet0/0/0/19 
1  0      0   GigabitEthernet0/0/0/0 - GigabitEthernet0/0/0/9 
2  1      0   TenGigE0/0/0/1
3  1      0   TenGigE0/0/0/0
RP/0/RSP0/CPU0:bfr01.60hudson01#

2.  See what drops the NP is registering:

RP/0/RSP0/CPU0:bfr01.60hudson01#show controllers np counters np1 location 0/0/CPU0 | i "DROP|DISCARD|NOT"
Wed Feb 16 00:59:26.456 EST
  31  PARSE_INGRESS_DROP_CNT                                541959           4
  33  RESOLVE_INGRESS_DROP_CNT                              137755           0
  34  RESOLVE_EGRESS_DROP_CNT                                    1           0
 286  DROP_IPV4_CHECKSUM_ERROR                                   1           0
 299  UNKNOWN_L2_ON_L3_DISCARD                               87006           1
 310  DROP_IPV4_NOT_ENABLED                                     66           0
 314  DROP_IPV4_NEXT_HOP_DOWN                                    1           0
 338  DROP_IPV6_NOT_ENABLED                                 450372           3
 348  MPLS_NOT_ENABLED_DROP                                      1           0
 371  L3_NOT_MYMAC                                          137755           0
RP/0/RSP0/CPU0:bfr01.60hudson01#