Hi All,
I have configured 1 vPC's between 2 Nexus 5596 and 1 stack C3750 switch. The links in the stack are distributed over both members.
Gi1/1/1 -> Eth 1/44 NX 5596-02
Gi 2/1/1 -> Eth 1/45 NX 5596-02
Gi 1/1/2 -> Eth 1/46 NX 5596-01
Gi 2/1/2 -> Eth 1/47 NX 5596-01
The same logic is for another stack C3750 to the same pair of Nexus 5596 switches.
The problem is that the links from the vPCs keep flapping at random moments - 1-2 times per hour.
The network is not loaded at this time and the same issue is on both vPC's.
the flaps in the nexus 5596 looks like this
%ETH_PORT_CHANNEL-5-PORT_DOWN: port-channel108: Ethernet1/44 is down
%ETH_PORT_CHANNEL-5-FOP_CHANGED: port-channel108: first operational port changed from Ethernet1/44 to Ethernet1/45
%ETHPORT-5-IF_DOWN_INITIALIZING: Interface Ethernet1/44 is down (Initializing)
%ETH_PORT_CHANNEL-5-PORT_UP: port-channel108: Ethernet1/44 is up
%ETHPORT-5-IF_UP: Interface Ethernet1/44 is up in mode trunk
On the stack is just up/down the pair interface.
I started few debugs on the stack and captured the folowing output:
C3750X-02#im_if_stack_relationship_add: Posting the ACP job for stack add for 5018.10902
im_if_stack_relationship_add: Posted the ACP job for stack add successfully
im_add_ifstackentry: higher_if_index = 5018 lower_if_index = 10902
im_add_ifstackentry: Failed to delete nolayerelem from NoLowerLayerTree for higher_ifIndex = 5018
im_add_ifstackentry: Failed to delete nolayerelem from NoHigherLayerTree for lower_ifIndex = 10902
im_add_ifstackentry: Deleted nolayerelems from NoHigherLayerTree and NoLowerLayerTree
im_add_ifstackentry: Failed to insert stackelem into StackTree
Jul 12 03:35:26.122: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet2/1/2, changed state to downim_if_stack_relationship_add: Posting the ACP job for stack add for 5018.10902
im_if_stack_relationship_add: Posted the ACP job for stack add successfully
im_add_ifstackentry: higher_if_index = 5018 lower_if_index = 10902
im_add_ifstackentry: Failed to delete nolayerelem from NoLowerLayerTree for higher_ifIndex = 5018
im_add_ifstackentry: Failed to delete nolayerelem from NoHigherLayerTree for lower_ifIndex = 10902
im_add_ifstackentry: Deleted nolayerelems from NoHigherLayerTree and NoLowerLayerTree
im_add_ifstackentry: Failed to insert stackelem into StackTree
Jul 12 03:35:29.058: %LINEPROTO-5-UPDOWN: Line protocol on Interface TenGigabitEthernet2/1/2, changed state to up
Do someone have any idea what happens here ?
The configuration is ok because i have another vPC connected to FEX's and is working fine.
Kind regards,
