NCS 540 XR 6.3.2 / Troubleshooting Interface input drops

[dgilbertson]

Would any have commands for the NCS 540 to view what drops are occurring on the router? 

show drops ;  command doesn't exist

show contr tengig 0/0/0/23 stats ; isn't showing any errors or drops

show contr ?  ; options and output is pretty cryptic

Any suggestions would be appreciated.

#sh int ten 0/0/0/23 | i drop
Fri Nov 30 21:33:40.617 UTC
11346325294 packets input, 3510712998344 bytes, 12759057 total input drops
0 drops for unrecognized upper-level protocol
331548436198 packets output, 74631515816304 bytes, 0 total output drops

[dgilbertson]

Digging through the community posts;  I did find this post with at least is leading me down the right path.

post from: IOS-XR: input drop が断続的にカウントアップする

#show netio drops interface tenGigE 0/0/0/23 location 0/0/cpu0
Fri Nov 30 22:25:29.840 UTC

--------------------------------------------------------------------------------
Interface: TenGigE0/0/0/23 (0x00000258)
--------------------------------------------------------------------------------

Interface input drops: 681451527 pkts

Caps <num> (Protocol <num> Chain):
-----------------------------------
DLL/function name Address Drop pkts Drop bytes
---------------------------------------- ---------- ---------- ----------

mpls <25> (mpls <13> decaps):
<unknown> 0x5a033b12 681451527 2230927114

[tkarnani]

can we check to see if this command is supported on your version of NCS?

show captured packets ingress location 0/x/cpu0

thanks

[dgilbertson]

That command does work.  Here's a snipit of the output.

#show captured packets ingress location 0/0/cpu0
Mon Dec 3 18:11:37.014 UTC
-------------------------------------------------------
packets dropped in hardware in the ingress direction
buffer overflow pkt drops:240996, current: 200, maximum: 200

[200] Dec 3 18:02:15.494, len: 77, hits: 1, buffhdr type: 1
i/p i/f: TenGigE0/0/0/17
punt reason: DROP_PACKET
Ingress Headers:
port_ifh: 0x228, sub_ifh: 0x0, bundle_ifh: 0x0
logical_port: 0x21, pd_pkt_type: 4
punt_reason: DROP_PACKET (0)
payload_offset: 29, l3_offset: 29
FTMH:
pkt_size: 0x6c, tc: 1, tm_act_type: 0, ssp: 0x21
PPH:
pph_fwd_code: CPU Trap (7), fwd_hdr_offset: 0
inlif: 0x0, vrf: 0xffff, rif: 0x61b
FHEI:
trap_code: Rx_UNKNOWN_PACKET (63), trap_qual: 33
[ether dst: ab00.0002.0000 src: cc8e.7169.9a10 type/len: 0x6002]

[dgilbertson]

Further snipit; looking at just that interface TenGig0/0/0/11 from that command output.   I remove the packet data as it's the same as what I already posted.  As far as the capture output.

[25] Dec 3 16:24:42.610, len: 77, hits: 1, buffhdr type: 1
i/p i/f: TenGigE0/0/0/11
...

[43] Dec 3 16:33:22.138, len: 77, hits: 1, buffhdr type: 1
i/p i/f: TenGigE0/0/0/11
...

[59] Dec 3 16:43:36.619, len: 77, hits: 1, buffhdr type: 1
i/p i/f: TenGigE0/0/0/11
punt reason: DROP_PACKET
...

[73] Dec 3 16:55:02.586, len: 77, hits: 1, buffhdr type: 1
i/p i/f: TenGigE0/0/0/11

...

[tkarnani]

Can you provide the hexdump?

keyword is in the same command.

we can inspect the packet and see what the interfaces doesn't like

[dgilbertson]

[8] Dec 3 16:24:42.610, len: 77, hits: 1, buffhdr type: 1
i/p i/f: TenGigE0/0/0/11
punt reason: DROP_PACKET
Ingress Headers:
port_ifh: 0x1f8, sub_ifh: 0x0, bundle_ifh: 0x0
logical_port: 0x1b, pd_pkt_type: 4
punt_reason: DROP_PACKET (0)
payload_offset: 29, l3_offset: 29
FTMH:
pkt_size: 0x6c, tc: 1, tm_act_type: 0, ssp: 0x1b
PPH:
pph_fwd_code: CPU Trap (7), fwd_hdr_offset: 0
inlif: 0x0, vrf: 0xffff, rif: 0x615
FHEI:
trap_code: Rx_UNKNOWN_PACKET (63), trap_qual: 27

ab000002 0000cc8e 7169999f 60023d00 07000000 01000303 00000200 02210003
00060000 00000000 0400023c 00050002 d8050600 02000107 0006cc8e 7169999f
64000179 90010101 91010240 09000000 00000000 00000000 00000000 00000000
00000000 00000000 0000

[tkarnani]

ok it seems the peer device is sending these packets

• Destination: DEC-MOP-Remote-Console (ab:00:00:02:00:00)
• Source: Cisco_69:99:9f (cc:8e:71:69:99:9f)
• Type: DEC DNA Remote Console (0x6002)

please turn it off.. i belive it is "no mop enabled" under the peer interface

[dgilbertson]

Good to know.  All of interfaces on this NCS 540 are v4 point-to-point.  None the less, I'll work on getting that disabled.  

[tkarnani]

Great, thanks