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ACI - Explanations of Packet Drop Faults in ACI

Authors
  • avatar
    Name
    Jimmy Lai
    Twitter

Introduction

Problem Description

[+] receiving F110176 & F110344 & F96760

moquery -c l2IngrPktsAg15min

moquery -d uni/tn-TENANT1/ap-APP1/epg-EPG2/CDl2IngrPktsAg15min | egrep 'dn|drop[P,R]|rep'

SSH to the leaf and run these commands.

ACI-LEAF# vsh_lc
module-1# show platform internal counters port <X>

Receiving faults F110344 and F110176 which relate to l2IngrBytes5min:dropRate. The l2IngrByte and l2IngrPkt faults can be cosmetic.

Due to ASIC limitation in -EX platform such as N9K-C93180YC-EX, N9K-C9336C-FX2-B, "Forward Drop" in the leaf command " vsh_lc -c 'show platform internal counters port X " is incremented by packets redirected to CPU even though those packets are not dropped.

https://www.cisco.com/c/en/us/support/docs/cloud-systems-management/application-policy-infrastructure-controller-apic/210539-Explanations-of-Packet-Drop-Faults-in-AC.html

Stated in the defect is how to prevent the faults:

  • Ignore faults related to l2IngrPkts Drops, or

  • Change the threshold for those faults, or

  • Squelch those faults (although they may come back if the threshold is crossed again)

Tenant > common > policies > monitor > 
default > state collection policy > 
application EPG (fv.AEPg)> part of ingress bytes > unclick warning

 

Tenant > common > policies > monitor 
> default > state collection policy 
> application EPG (fv.AEPg)> part of ingress packet > unclick warning

 

Tenant > common > policies > monitor 
> default > state collection policy 
> vlan.cktep > ingress bytes > unclick warning

 

Tenant > common > policies > monitor 
> default > state collection policy > vlan.cktep 
> ingress packet > unclick warning

 

Fabric > access policies > policies > monitor 
> default > state collection policy > layer1 physical interface configuration 
> ingress drop packet > forwarding drop packet > unclick warning

[+] F96760

Recommended Action: Check the values of 'Egress Buffer Drop Packets' statistical counter and either correct the conditions that cause the counter values to cross certain threshold levels, or adjust the threshold values in monitoring policies.

this fault F96760 means that the default monitoring policy threshold (10/s) was exceeded.

There is a way to remove the fault in ACI:


* On the APIC, click FABRIC > FABRIC POLICIES > Policies > Monitoring > default > Stats Collection Polices

* Change Monitoring Object (drop down menu at top) to “Qos Interface Class (qosm.IfClass)”

* Click the Edit Stats Type button (The pencil icon) next to Stats Type.

* Uncheck egress packets.

* Click Submit Again, nothing to worry about from the ACI side

Explanations of Packet Drop Faults in ACI