Guest

Preview Tool

Cisco Bug: CSCvi51544 - Frames from native-vlan are egressing with dot1q header

Last Modified

Aug 14, 2018

Products (50)

  • Cisco Nexus 9000 Series Switches
  • Cisco Nexus 3548-X Switch
  • Cisco Nexus 3548 Switch
  • Cisco Nexus 9516 Switch
  • Cisco Nexus 92304QC Switch
  • Cisco Nexus 9396PX Switch
  • Cisco Nexus 3132Q-V Switch
  • Cisco Nexus 9396TX Switch
  • Cisco Nexus 93108TC-FX Switch
  • Cisco Nexus 92160YC-X Switch
View all products in Bug Search Tool Login Required

Known Affected Releases

7.0(3)I7(1) 7.0(3)I7(3)

Description (partial)

Symptom:
Packets ingressing the Nexus 9200/9300 switch and tagged with native-vlan when egressing out of the interface are encapsulated with dot1q header. The port-channel interface from which the packets are forwarded out is a layer 2 trunk port-channel which allows only native vlan.

Conditions:
This condition is specific to interfaces configured after an interface is associated to the FEX fabric unit/slice/slice_port = 0/0/0. This interface is configured as fex-fabric port and the port-channel which is forwarding the packets is a newly created port-channel configured after fex-fabric port has been configured.

interface EthernetX/Y
  description FEX
  switchport mode fex-fabric <<<
  switchport access vlan XXX
  fex associate XXX
  spanning-tree port type edge
  no snmp trap link-status
  no shutdown

** Interface does not have to be in an operational state to cause this condition.

This issue is specific to following models of Nexus 9200/9300 Switches

Nexus 93180YC 
Nexus 92160YC
N9K-C9272Q
N9K-C9236C
N9K-C92304QC
N9K-C92300YC
N9K-C9232C
N9K-C93108TC-EX
N9K-C93180LC-EX

Line cards
N9K-X9732C-EX
N9K-X9736C-EX
N9K-X9732C-EXM
N9K-X97160YC-EX
Bug details contain sensitive information and therefore require a Cisco.com account to be viewed.

Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
  • Severity
  • Known Fixed Releases
  • Related Community Discussions
  • Number of Related Support Cases
Bug information is viewable for customers and partners who have a service contract. Registered users can view up to 200 bugs per month without a service contract.