why vPC member ports are all down ?

junhyeok89 · ‎01-28-2016

Hi guys

I really would like to your help..

<Processes>

1. Disconnected N7K's vPC member ports
2. Also Disconnected Keepalive and then Peer-link
3. OS upgraded N7K-2
4. After upgraded, I connect Keepalive first and then peer-link ---> Problem occur !!!
5. .......omit...

<Problem>

When I connected peer-link again..., vPC member ports all down. after few minutes, be up state...(about..2 minutes..)
I don't understand that... why all vPC member ports down.....

Please tell me something advice...T^T

ping loss...

<Topology>

<vPC Configuration>

[N7K-1]

feature vpc

vpc domain 10
role priority 100
peer-keepalive destination 10.10.10.2 source 10.10.10.1 vrf keepalive-vrf

interface e3/3
description ## vPC Keep-Alive Link ##
no cdp enable
channel-group 1 mode active
no shutdown

interface port-channel1
description # PC-1 # vPC-Keep-Alive-Link
vrf member keepalive-vrf
ip address 10.10.10.1/30

interface Ethernet4/1
description ## vPC Peer Link ##
no cdp enable
switchport
switchport mode trunk
channel-group 2 mode active
no shutdown

interface port-channel2
description # PC-2 # vPC-Peer-Link
switchport
switchport mode trunk
spanning-tree cost 1400
spanning-tree port type network
vpc peer-link

interface Ethernet3/4
channel-group 100 mode active

interface port-channel100
description # PC-100 # C4948
switchport
switchport mode trunk
vpc 100

[N7K-2]

feature vpc

vrf context keepalive-vrf
vpc domain 10
role priority 105
no auto-recover
peer-keepalive destination 10.10.10.1 source 10.10.10.2 vrf keepalive-vrf

interface e3/23
description ## vPC Keep-Alive Link ##
no cdp enable
channel-group 1 mode active
no shutdown

interface port-channel1
description # PC-1 # vPC-Keep-Alive-Link
vrf member keepalive-vrf
ip address 10.10.10.2/30

interface Ethernet4/5
description ## vPC Peer Link ##
no cdp enable
switchport
switchport mode trunk
channel-group 2 mode active
no shutdown

interface port-channel2
description # PC-2 # vPC-Peer-Link
switchport
switchport mode trunk
spanning-tree cost 1400
spanning-tree port type network
vpc peer-link

interface Ethernet3/24
channel-group 100 mode active

interface port-channel100
description # PC-100 # C4948
switchport
switchport mode trunk
vpc 100

and running HSRP

InayathUlla Sharieff · ‎01-28-2016

My assumption is that you might be ending in the dual active scenario due to which the secondary vpc box is suspending all the members link.

Could you please answer me the following:-

1- Whats the current situation? Is the issue still persist are is it resolved?

2- If it is not resolved what is the status of VPC( Show vpc brief on both the devices)?

3- On Which VPC device/box you are seeing the members going down?

Regards

Inayath

junhyeok89 · ‎01-28-2016

1- Whats the current situation? Is the issue still persist are is it resolved?

-> Current state is fine but why all vPC member ports on both switches when Peer-link became UP

2- If it is not resolved what is the status of VPC( Show vpc brief on both the devices)?

->

<N7K-1>

switch# show vpc
Legend:
(*) - local vPC is down, forwarding via vPC peer-link

vPC domain id : 10
Peer status : peer adjacency formed ok
vPC keep-alive status : peer is alive
Configuration consistency status : success
Per-vlan consistency status : success
Type-2 consistency status : success
vPC role : primary, operational secondary
Number of vPCs configured : 1
Peer Gateway : Disabled
Dual-active excluded VLANs : -
Graceful Consistency Check : Enabled
Auto-recovery status : Disabled

vPC Peer-link status
---------------------------------------------------------------------
id Port Status Active vlans
-- ---- ------ --------------------------------------------------
1 Po2 up 1,10

vPC status
----------------------------------------------------------------------
id Port Status Consistency Reason Active vlans
-- ---- ------ ----------- ------ ------------
100 Po100 up success success 1,10
switch#

<N7K-2>

switch_2# show vpc
Legend:
(*) - local vPC is down, forwarding via vPC peer-link

vPC domain id : 10
Peer status : peer adjacency formed ok
vPC keep-alive status : peer is alive
Configuration consistency status : success
Per-vlan consistency status : success
Type-2 consistency status : success
vPC role : secondary, operational primary
Number of vPCs configured : 1
Peer Gateway : Disabled
Dual-active excluded VLANs : -
Graceful Consistency Check : Enabled
Auto-recovery status : Enabled (timeout = 240 seconds)

vPC Peer-link status
---------------------------------------------------------------------
id Port Status Active vlans
-- ---- ------ --------------------------------------------------
1 Po2 up 1,10

vPC status
----------------------------------------------------------------------
id Port Status Consistency Reason Active vlans
-- ---- ------ ----------- ------ ------------
100 Po100 up success success 1,10
switch_2#

3- On Which VPC device/box you are seeing the members going down?

-> both switches....

Rajeshkumar Gatti · ‎01-29-2016

Both sides will flap the VPC links when recovering from dual active state. This is expected behavior but can be avoided by following the steps mentioned at the link below w.r.t vpc sticky bit

Doc for avoiding vpc flap on both 7ks

-Raj

junhyeok89 · ‎01-31-2016

Thank you so much, Raj

I have a one more question

After flap on both N7Ks, took much time untill UP state of vPC member ports(about 48s ~ 60s)

Is this right????

-Jun

Rajeshkumar Gatti · ‎02-01-2016

un,

The delay restore timer is most likely kicking in and delaying the VPC bring up. It is an expected behavior.
You can run the below command and go through the sequence of events for vpc bring up-
sh sys intern vpcm event-history interactions

You should see a sequence like below - the newest messages are on the top.
7) Event:E_DEBUG, length:30, at 955875 usecs after Mon Apr 14 14:11:49 2014
    [104] Reiniting down vpc : 100
8) Event:E_DEBUG, length:29, at 955873 usecs after Mon Apr 14 14:11:49 2014
    [104] Reiniting down vpc : 20
9) Event:E_DEBUG, length:29, at 955871 usecs after Mon Apr 14 14:11:49 2014 >>> reiniting the VPC
    [104] Reiniting down vpc : 10
10) Event:E_DEBUG, length:37, at 955834 usecs after Mon Apr 14 14:11:49 2014 >>D_RESTORE 30sec ended
    [104] vPC restore delay timer expired
11) Event:E_DEBUG, length:46, at 947738 usecs after Mon Apr 14 14:11:19 2014 >>D_RESTORE 30sec started
    [104] Sending mts message to delay vPC bringup

These event logs can roll over if there were a lot of VPC events incase if you don't see messages for the corresponding time stamp.

-Raj