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Cisco Bug: CSCus76724 - NVT-DC1:PVLAN traffic block-hole upon Primary VLAN remove/add

Last Modified

Mar 09, 2018

Products (1)

  • Cisco Nexus 7000 Series Switches

Known Affected Releases


Description (partial)

On M1XL linecards, when some vlan config causes a private-vlan association to be non-operational , private-vlan trunk secondary port sees traffic loss.  Similarly, when the trunk association is unconfigured and re-configured on private-vlan trunk-secondary port, the issue might be observed.

This issue is seen on M1XL linecards. Will not be seen with M1 and F-series line cards

Example config and trigger:
switch(config-if)# show running-config interface e3/3

!Command: show running-config interface Ethernet3/3
!Time: Wed Feb  4 00:38:51 2015

version 6.2(12)

interface Ethernet3/3
  switchport mode private-vlan trunk secondary
  switchport private-vlan association trunk 2 3
  no shutdown

The issue will be seen after any of the following triggers

1.  Delete and recreate of primary vlan
switch(config-if)# no vlan 2
switch(config)# vlan 2
switch(config-vlan)# private-vlan primary
switch(config-vlan)# private-vlan association 3
switch(config-vlan)# ex

2. Delete and recreate secondary vlan
switch(config-if)# no vlan 3
switch(config)# vlan 3
switch(config-vlan)# private-vlan isolated
switch(config-vlan)# ex

3. Delete and re-add trunk association on the port
switch(config)# int e3/3
switch(config-if)# no switchport private-vlan association trunk 2 3
switch(config-if)#  switchport private-vlan association trunk 2 3
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