Nexus 7k 10gb Interface Errors

[ssmith2507]

Hi, I have seen the following alarms on a 10gb Interface but can't find anything on the web for it.

The interface is showing input errors and giants - numbers match.

Any advise on why this is happening or to point me to maybe a doc etc.. would be appreciated.

I have included the running config below it as well:

Ethernet1/2 is up

  Dedicated Interface

  Belongs to Po102

  Hardware: 10000 Ethernet, address: d0d0.fd94.b085 (bia d0d0.fd94.b085)

  Description

  MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec

  reliability 255/255, txload 1/255, rxload 1/255

  Encapsulation ARPA

  Port mode is trunk

  full-duplex, 10 Gb/s, media type is 10G

  Beacon is turned off

  Auto-Negotiation is turned off

  Input flow-control is off, output flow-control is off

  Rate mode is dedicated

  Switchport monitor is off

  EtherType is 0x8100

  Last link flapped 33week(s) 5day(s)

  Last clearing of "show interface" counters 53w2d

  30 seconds input rate 5420408 bits/sec, 1754 packets/sec

  30 seconds output rate 64599872 bits/sec, 17182 packets/sec

  Load-Interval #2: 5 minute (300 seconds)

    input rate 5.14 Mbps, 1.74 Kpps; output rate 64.71 Mbps, 14.42 Kpps

  RX

    66753463839 unicast packets  102434389 multicast packets  202558 broadcast packets

    66856100786 input packets  38674338907086 bytes

    192833 jumbo packets  0 storm suppression packets

    0 runts  9054401 giants  0 CRC  0 no buffer

    9054401 input error  0 short frame  0 overrun   0 underrun  0 ignored

    0 watchdog  0 bad etype drop  0 bad proto drop  0 if down drop

    0 input with dribble  0 input discard

    0 Rx pause

  TX

    145461457591 unicast packets  39476017 multicast packets  11699 broadcast packets

    145500945307 output packets  65001811350919 bytes

    10583652 jumbo packets

    0 output error  0 collision  0 deferred  0 late collision

    0 lost carrier  0 no carrier  0 babble  0 output discard

    0 Tx pause

  15 interface resets

----------------------------------------------------------------------------------------------------------------------------------------

interface Ethernet1/2

  description

  switchport mode trunk

  switchport trunk native vlan 999

  switchport trunk allowed vlan 12-13,511,589,591

  link debounce time 10

  channel-group 102 mode active

  no shutdown

Thanks.

[Peter Koltl]

The other side sends jumbo frames because its MTU is set to bigger.

[ssmith2507]

Configuration is identical at both sides.

No MTU settings are specified (on the interfaces with issues) and both boxes running the same version of NX code.

Any more advice would be appreciated.

It was really the Giants and Input errors I'm concerned about. Both incrementing at the same time.

[Peter Koltl]

show interface

on the other side?

[Peter Koltl · Accepted solution]

http://www.cisco.com/en/US/partner/docs/switches/datacenter/sw/6_x/nx-os/qos/configuration/guide/nt_qos.html

The switch cannot have two ports in the same Layer 2 domain with different maximum transmission units (MTUs). A per-physical Ethernet interface MTU is not supported. Instead, the MTU is set according to the QoS classes. You modify the MTU by setting class and policy maps. When you show the interface settings, a default MTU of 1500 is displayed for physical Ethernet interfaces.

Please check on both sides:

show run all | include jumbomtu

show queuing interface ethernet1/2

show class-map type network-qos
     Displays the type network qos class maps.

show policy-map type network-qos
     Displays the type network qos policy maps.

show policy-map system type network-qos
     Displays the active type network qos class maps.

[jerome.parisse]

Hi

Sorry for bringing up an old post, but I am facing the same issue and can't find a solution.

I have a stack of 3750 connected to a couple of Nexus 3064. 
Here are the results of the commands Peter gave :

nexus01.mar02# show run all | include jumbomtu
system jumbomtu 9216

nexus01.mar02# sh queuing | i MTU
HW MTU of Ethernet1/1 : 9216 bytes
HW MTU of Ethernet1/2 : 9216 bytes
[...]
HW MTU of Ethernet1/45 : 9216 bytes
HW MTU of Ethernet1/46 : 9216 bytes
HW MTU of Ethernet1/47 : 9216 bytes
HW MTU of Ethernet1/48 : 9216 bytes
HW MTU of Ethernet1/49 : 9216 bytes
HW MTU of Ethernet1/50 : 9216 bytes
HW MTU of Ethernet1/51 : 9216 bytes
HW MTU of Ethernet1/52 : 9216 bytes
nexus01.mar02#

nexus01.mar02# show class-map type network-qos

  Type network-qos class-maps
  ===========================
  class-map type network-qos class-default
    match qos-group 0

nexus01.mar02# show policy-map type network-qos

  Type network-qos policy-maps
  ============================
  policy-map type network-qos jumbo-policy
      Description: JUMBO FRAMES
    class type network-qos class-default
      mtu 9216
  policy-map type network-qos default-nq-policy
    class type network-qos class-default
      mtu 1500

nexus01.mar02# show policy-map system type network-qos

  Type network-qos policy-maps
  ============================
  policy-map type network-qos jumbo-policy
      Description: JUMBO FRAMES
    class type network-qos class-default
      match qos-group 0
      mtu 9216

nexus01.mar02#

So as far as I understand, the qos policy is set correctly, the reported MTU is 9216 from queuing perspective

When I run a "show interface", it shows a MTU of 1500 for the incriminated interfaces (but not for all...) :
nexus01.mar02# sh int e1/45-52 | i MTU
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 1000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 40000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 40000000 Kbit, DLY 10 usec
MTU 9216 bytes, BW 40000000 Kbit, DLY 10 usec
MTU 9216 bytes, BW 40000000 Kbit, DLY 10 usec
nexus01.mar02#
nexus01.mar02# sh int po10,po45,po47 | i MTU
MTU 9216 bytes, BW 80000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 2000000 Kbit, DLY 10 usec
MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
nexus01.mar02#

Theses interfaces are part of a PortChanel, which is in VLAN trunk mode (802.1q). I tried on interfaces "standalone" in access mode, I have the same results :

jparisse@ptb-it04:~$ ping 192.168.1.199 -s 1472 -M do
PING 192.168.1.199 (192.168.1.199) 1472(1500) bytes of data.
^C
--- 192.168.1.199 ping statistics ---
9 packets transmitted, 0 received, 100% packet loss, time 8062ms

jparisse@ptb-it04:~$

nexus01.mar02# sh int e1/1-2 | i giants
    0 runts 9 giants 0 CRC 0 no buffer
    0 runts 0 giants 0 CRC 0 no buffer
nexus01.mar02#

jparisse@ptb-it04:~$ ping 192.168.1.199 -s 1455 -M do
PING 192.168.1.199 (192.168.1.199) 1455(1483) bytes of data.
^C
--- 192.168.1.199 ping statistics ---
3 packets transmitted, 0 received, 100% packet loss, time 1999ms

jparisse@ptb-it04:~$ ping 192.168.1.199 -s 1454 -M do
PING 192.168.1.199 (192.168.1.199) 1454(1482) bytes of data.
1462 bytes from 192.168.1.199: icmp_seq=1 ttl=128 time=0.630 ms
1462 bytes from 192.168.1.199: icmp_seq=2 ttl=128 time=0.540 ms
1462 bytes from 192.168.1.199: icmp_seq=3 ttl=128 time=0.569 ms
^C
--- 192.168.1.199 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 1998ms
rtt min/avg/max/mdev = 0.540/0.579/0.630/0.046 ms
jparisse@ptb-it04:~$

I probably missed something somewhere in the configuration, but I can't figure out what

Thanks a lot in advance for any clue on how to solve this issue

Edit 2016-13-10 : An NX-OS upgrade did the trick, now running 7.0(3)I2(4), previous one was 7.0(3)I2(2a)