I have 2 9500 stacks interconnected with 4 10G cables, bundled with LACP ( Portchannel 95)
The problem is that when I propagate a VLAN over the Port-Channel, VLAN 4 and the VLAN that I am passing, today VLAN 38, get blocked by spanning-tree and recovers a minute after.
*Jul 24 23:53:13.562: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan38, changed state to up
*Jul 24 23:54:52.902: %SPANTREE-2-BLOCK_PVID_PEER: Blocking Port-channel95 on VLAN0038. Inconsistent peer vlan.
*Jul 24 23:54:52.902: %SPANTREE-2-BLOCK_PVID_LOCAL: Blocking Port-channel95 on VLAN0004. Inconsistent local vlan.
*Jul 24 23:54:54.903: %LINK-3-UPDOWN: Interface Vlan38, changed state to down
*Jul 24 23:54:55.903: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan38, changed state to down
*Jul 24 23:55:07.902: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking Port-channel95 on VLAN0038. Port consistency restored.
*Jul 24 23:55:07.902: %SPANTREE-2-UNBLOCK_CONSIST_PORT: Unblocking Port-channel95 on VLAN0004. Port consistency restored.
*Jul 24 23:55:11.574: %LINK-3-UPDOWN: Interface Vlan38, changed state to up
*Jul 24 23:55:12.575: %LINEPROTO-5-UPDOWN: Line protocol on Interface Vlan38, changed state to up
Native VLAN 4 is the same on both stacks, and all VLANs in the trunk exist on L2.
Could you advise, why is this behavior present?
>stack1 configuration
spanning-tree mode rapid-pvst
spanning-tree extend system-id
errdisable recovery cause udld
errdisable recovery cause bpduguard
errdisable recovery cause l2ptguard
interface Port-channel95
switchport trunk native vlan 4
switchport trunk allowed vlan 4,8,16,38,43,48,50,63-66,93,110-115,220,241
switchport mode trunk
>stack2 configuration
spanning-tree mode rapid-pvst
spanning-tree loopguard default
spanning-tree portfast default
spanning-tree portfast bpduguard default
spanning-tree extend system-id
errdisable recovery cause udld
errdisable recovery cause bpduguard
errdisable recovery cause l2ptguard
interface Port-channel95
switchport trunk native vlan 4
switchport trunk allowed vlan 4,8,16,38,43,48,50,63-66,93,110-115,220,241
switchport mode trunk
Thank you so much for your help!
