Input errors on my с6500

[Alex M]

Hello!

I have configured this scheme:

| c6500 |g4/47|------[trunk - 300 Mb/s MAX]------|g0/0/3| ASR1002f |

After that, I saw that "Input errors" counter increased on the c6500 - g4/47. The g0/0/3 on the ASR looks without problem.
What's more, packet loss doesn't occur on that interface and customers don't complain to me.

g4/47 (Located on WS-X6748-GE-TX module.)

GigabitEthernet4/47 is up, line protocol is up (connected)
  Hardware is C6k 1000Mb 802.3, address is 0012.80c7.04de (bia 0012.80c7.04de)
  Description: Link to asr1002f-1
  MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec, 
     reliability 255/255, txload 14/255, rxload 41/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 1000Mb/s, media type is 10/100/1000BaseT
  input flow-control is off, output flow-control is off
  Clock mode is auto
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input never, output never, output hang never
  Last clearing of "show interface" counters 09:18:10
  Input queue: 0/2000/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  5 minute input rate 160938000 bits/sec, 20173 packets/sec
  5 minute output rate 58258000 bits/sec, 17267 packets/sec
     154295390 packets input, 135788600661 bytes, 0 no buffer
     Received 4121 broadcasts (3863 multicasts)
     0 runts, 0 giants, 0 throttles 
     367 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 0 multicast, 0 pause input
     0 input packets with dribble condition detected
     138657812 packets output, 67045673270 bytes, 0 underruns
     0 output errors, 0 collisions, 0 interface resets
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 PAUSE output
     0 output buffer failures, 0 output buffers swapped out

g0/0/3

GigabitEthernet0/0/3 is up, line protocol is up 
  Hardware is 4XGE-BUILT-IN, address is 4055.399d.9203 (bia 4055.399d.9203)
  Description: Link to c6506E
  MTU 1500 bytes, BW 1000000 Kbit/sec, DLY 10 usec, 
     reliability 255/255, txload 40/255, rxload 14/255
  Encapsulation 802.1Q Virtual LAN, Vlan ID  1., loopback not set
  Keepalive not supported 
  Full Duplex, 1000Mbps, link type is auto, media type is T
  output flow-control is on, input flow-control is on
  ARP type: ARPA, ARP Timeout 04:00:00
  Last input 00:00:10, output 00:00:11, output hang never
  Last clearing of "show interface" counters never
  Input queue: 0/375/0/0 (size/max/drops/flushes); Total output drops: 0
  Queueing strategy: fifo
  Output queue: 0/40 (size/max)
  30 second input rate 57823000 bits/sec, 16808 packets/sec
  30 second output rate 159113000 bits/sec, 19761 packets/sec
     2576235394 packets input, 1105227377945 bytes, 0 no buffer
     Received 269 broadcasts (0 IP multicasts)
     0 runts, 0 giants, 0 throttles
     0 input errors, 0 CRC, 0 frame, 0 overrun, 0 ignored
     0 watchdog, 52402 multicast, 0 pause input
     2888300571 packets output, 2688926885221 bytes, 0 underruns
     0 output errors, 0 collisions, 6 interface resets
     0 unknown protocol drops
     0 babbles, 0 late collision, 0 deferred
     0 lost carrier, 0 no carrier, 0 pause output
     0 output buffer failures, 0 output buffers swapped out

I looked at sh int g4/47 counters errors and didn't see anything wrong:

Port                     Align-Err             FCS-Err            Xmit-Err             Rcv-Err           UnderSize         OutDiscards
Gi4/47                           0                   0                   0                 377                   0                   0

Port                    Single-Col           Multi-Col            Late-Col          Excess-Col           Carri-Sen               Runts              Giants
Gi4/47                           0                   0                   0                   0                   0                   0                   0

Port                   SQETest-Err         Deferred-Tx        IntMacTx-Err        IntMacRx-Err          Symbol-Err
Gi4/47                           0                   0                   0                   0                   0

g4.47

interface GigabitEthernet4/47
 description Link to asr1002f-1
 switchport
 switchport trunk encapsulation dot1q
 switchport trunk native vlan 666
 switchport trunk allowed vlan 115,200
 switchport mode trunk
 switchport nonegotiate
 logging event link-status
end

g0/0/3

interface GigabitEthernet0/0/3
 description Link to c6506E
 no ip address
 load-interval 30
 negotiation auto
end

I tried to replace the cable and the SFP on ASR but it didn't help. It may be some problem with hardware, I don't know.
I think it looks like a bug in IOS 12.2(33)SXI6. Did anyone else encounter this problem?

[Leo Laohoo]

On the 6500, post the complete output to the command "sh count interface Gi4/47".

[Alex M]

Thanks for your reply!

c6506E#sh counters interface g4/47
64 bit counters:
 0. rxHCTotalPkts = 3572827588
 1. txHCTotalPkts = 3166486301
 2. rxHCUnicastPkts = 3572721724
 3. txHCUnicastPkts = 3166381281
 4. rxHCMulticastPkts = 50986
 5. txHCMulticastPkts = 57433
 6. rxHCBroadcastPkts = 54860
 7. txHCBroadcastPkts = 47605
 8. rxHCOctets = 3368723832656
 9. txHCOctets = 1355132564976
10. rxTxHCPkts64Octets = 217593864
11. rxTxHCPkts65to127Octets = 2310681881
12. rxTxHCPkts128to255Octets = 570564055
13. rxTxHCPkts256to511Octets = 435489113
14. rxTxHCpkts512to1023Octets = 357469891
15. rxTxHCpkts1024to1518Octets = 2480944478
16. txHCTrunkFrames = 3166436388
17. rxHCTrunkFrames = 3572780520
18. rxHCDropEvents = 0
32 bit counters:
 0. rxCRCAlignErrors = 0
 1. rxUndersizedPkts = 0
 2. rxOversizedPkts = 0
 3. rxFragmentPkts = 0
 4. rxJabbers = 0
 5. txCollisions = 0
 6. ifInErrors = 17727
 7. ifOutErrors = 0
 8. ifInDiscards = 0
 9. ifInUnknownProtos = 0
10. ifOutDiscards = 0
11. txDelayExceededDiscards = 0
12. txCRC = 0
13. linkChange = 95128
14. wrongEncapFrames = 0
All Port Counters
 1. InPackets = 3572827588
 2. InOctets = 3368723832656
 3. InUcastPkts = 3572721724
 4. InMcastPkts = 50986
 5. InBcastPkts = 54860
 6. OutPackets = 3166486301
 7. OutOctets = 1355132564976
 8. OutUcastPkts = 3166381281
 9. OutMcastPkts = 57433
10. OutBcastPkts = 47605
11. AlignErr = 0
12. FCSErr = 0
13. XmitErr = 0
14. RcvErr = 17727
15. UnderSize = 0
16. SingleCol = 0
17. MultiCol = 0
18. LateCol = 0
19. ExcessiveCol = 0
20. CarrierSense = 0
21. Runts = 0
22. Giants = 0
23. InDiscards = 0
24. OutDiscards = 0
25. InErrors = 17727
26. OutErrors = 0
27. InUnknownProtos = 0
28. txCRC = 0
29. TrunkFramesTx = 3166436388
30. TrunkFramesRx = 3572780520
31. WrongEncap = 0
32. Broadcast_suppression_discards = 0
33. Multicast_suppression_discards = 0
34. Unicast_suppression_discards = 0
35. rxTxHCPkts64Octets = 217593864
36. rxTxHCPkts65to127Octets = 2310681881
37. rxTxHCPkts128to255Octets = 570564055
38. rxTxHCPkts256to511Octets = 435489113
39. rxTxHCpkts512to1023Octets = 357469891
40. rxTxHCpkts1024to1518Octets = 2480944478
41. DropEvents = 0
42. CRCAlignErrors = 0
43. UndersizedPkts = 0
44. OversizedPkts = 0
45. FragmentPkts = 0
46. Jabbers = 0
47. Collisions = 0
48. DelayExceededDiscards = 0
49. bpduOutlost = 0
50. qos0Outlost = 0
51. qos1Outlost = 0
52. qos2Outlost = 0
53. qos3Outlost = 0
54. qos4Outlost = 0
55. qos5Outlost = 0
56. qos6Outlost = 0
57. qos7Outlost = 0
58. qos8Outlost = 0
59. qos9Outlost = 0
60. qos10Outlost = 0
61. qos11Outlost = 0
62. qos12Outlost = 0
63. qos13Outlost = 0
64. qos14Outlost = 0
65. qos15Outlost = 0
66. qos16Outlost = 0
67. qos17Outlost = 0
68. qos18Outlost = 0
69. qos19Outlost = 0
70. qos20Outlost = 0
71. qos21Outlost = 0
72. qos22Outlost = 0
73. qos23Outlost = 0
74. qos24Outlost = 0
75. qos25Outlost = 0
76. qos26Outlost = 0
77. qos27Outlost = 0
78. qos28Outlost = 0
79. qos29Outlost = 0
80. qos30Outlost = 0
81. qos31Outlost = 0
82. bpduCbicOutlost = 0
83. qos0CbicOutlost = 0
84. qos1CbicOutlost = 0
85. qos2CbicOutlost = 0
86. qos3CbicOutlost = 0
87. bpduInlost = 0
88. qos0Inlost = 0
89. qos1Inlost = 0
90. qos2Inlost = 0
91. qos3Inlost = 0
92. qos4Inlost = 0
93. qos5Inlost = 0
94. qos6Inlost = 0
95. qos7Inlost = 0
96. qos8Inlost = 0
97. qos9Inlost = 0
98. qos10Inlost = 0
99. qos11Inlost = 0
100. qos12Inlost = 0
101. qos13Inlost = 0
102. qos14Inlost = 0
103. qos15Inlost = 0
104. qos16Inlost = 0
105. qos17Inlost = 0
106. qos18Inlost = 0
107. qos19Inlost = 0
108. qos20Inlost = 0
109. qos21Inlost = 0
110. qos22Inlost = 0
111. qos23Inlost = 0
112. qos24Inlost = 0
113. qos25Inlost = 0
114. qos26Inlost = 0
115. qos27Inlost = 0
116. qos28Inlost = 0
117. qos29Inlost = 0
118. qos30Inlost = 0
119. qos31Inlost = 0
120. pqueInlost = 0
121. Overruns = 0
122. maxIndex = 0

[Leo Laohoo]

 0. rxCRCAlignErrors = 0
 1. rxUndersizedPkts = 0
 2. rxOversizedPkts = 0
 3. rxFragmentPkts = 0
 4. rxJabbers = 0
 5. txCollisions = 0
 6. ifInErrors = 17727
 7. ifOutErrors = 0
 8. ifInDiscards = 0
 9. ifInUnknownProtos = 0
10. ifOutDiscards = 0
11. txDelayExceededDiscards = 0
12. txCRC = 0
13. linkChange = 95128
14. wrongEncapFrames = 0
All Port Counters
11. AlignErr = 0
12. FCSErr = 0
13. XmitErr = 0
14. RcvErr = 17727
15. UnderSize = 0
16. SingleCol = 0
17. MultiCol = 0
18. LateCol = 0
19. ExcessiveCol = 0
20. CarrierSense = 0
21. Runts = 0
22. Giants = 0
23. InDiscards = 0
24. OutDiscards = 0
25. InErrors = 17727
26. OutErrors = 0
27. InUnknownProtos = 0
28. txCRC = 0
31. WrongEncap = 0

It's not CRC error.  It's not Collision.  It's not "unknown protocol drop".   It's not QoS-related either.

So this means it's not Layer 1 (Physical Layer) issue.  I don't believe it's a Layer 2 issue either but something is definitely being dropped from the switch side and the culprit is the router.  

[Alex M]

I think you are right! I remembered ERSPAN was configured on the ARS g0/0/3 port. But there isn't any ERSPAN commands in the ASR config now. However, sh platform hardware qfp active feature erspan state on the ASR gets me response:

ERSPAN State:
 Status : Active
......

I'm going to reboot the ASR, may be it helps.

[Leo Laohoo · Accepted solution]

If the reboot fixes this issue then report this to Cisco as this could be a bug.

[Alex M]

OK. Thank you very much for your replies!

[Alex M]

So. I've reboot my ASR. But it didn't resolve the problem. After that, I changed IOS on the ASR and there aren't errors now. Thank you very much for your replies!

[Leo Laohoo · Accepted solution]

Please don't forget to mark this thread as "Answered".

[Leo Laohoo]

Thanks for taking the time to rate our posts, Alex.  :)