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Replies

Nexus 5548 VPC issue

dclee
Level 1
Level 1

We have 2 Nexus 5548's operating in VPC mode for our VMWare environment. its been working well for quite some time now.

But I noticed that just recently VPC10 is down, which is our connection back to one side of our NetApp SAN. The physical ints

are up on both sides and all appears well.

Any help would be appreciated.

-----------------------------------------------------------------------------------------

NEX1# sh vpc brief
Legend:
                (*) - local vPC is down, forwarding via vPC peer-link

vPC domain id                   : 100
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
Number of vPCs configured       : 9
Peer Gateway                    : Disabled
Dual-active excluded VLANs      : -
Graceful Consistency Check      : Enabled

vPC Peer-link status
---------------------------------------------------------------------
id   Port   Status Active vlans
--   ----   ------ --------------------------------------------------
1    Po100  up     1,220-222

vPC status
----------------------------------------------------------------------------
id     Port        Status Consistency Reason                     Active vlans
------ ----------- ------ ----------- -------------------------- -----------
10     Po10        down*  success     success                    -
20     Po20        up     success     success                    220
30     Po30        up     success     success                    1,220-222

NEX1# sh vpc consistency-parameters vpc 10

    Legend:
        Type 1 : vPC will be suspended in case of mismatch

Name                        Type  Local Value            Peer Value
-------------               ----  ---------------------- -----------------------
Shut Lan                    1     No                     No
STP Port Type               1     Default                Default
STP Port Guard              1     None                   None
STP MST Simulate PVST       1     Default                Default
lag-id                      1     [(1, 2-a0-98-11-24-9c, [(1, 2-a0-98-11-24-9c,
                                   1, 0, 0), (7f9b,       1, 0, 0), (7f9b,
                                  0-23-4-ee-be-64, 800a, 0-23-4-ee-be-64, 800a,
                                   0, 0)]                 0, 0)]
mode                        1     active                 active
Speed                       1     10 Gb/s                10 Gb/s
Duplex                      1     full                   full
Port Mode                   1     access                 access
MTU                         1     1500                   1500
Allowed VLANs               -     220                    220
Local suspended VLANs       -     -                      -

------------------------------------------------------------------------------------------------------

interface Ethernet1/3

  description NETAPP_NODE_A_VIF10G-1

  switchport access vlan 220

  channel-group 10 mode active

------------------------------------------------------------------------------------------------------------

interface port-channel10

  description NETAPP_NODE_A

  vpc 10

  switchport access vlan 220

-------------------------------------------------------------------------------------------------------------

sh port-channel summary

Flags:  D - Down        P - Up in port-channel (members)

        I - Individual  H - Hot-standby (LACP only)

        s - Suspended   r - Module-removed

        S - Switched    R - Routed

        U - Up (port-channel)

--------------------------------------------------------------------------------

Group Port-       Type     Protocol  Member Ports

      Channel

--------------------------------------------------------------------------------

10    Po10(SD)    Eth      LACP      Eth1/3(I)

1 Accepted Solution

Accepted Solutions

stanti
Cisco Employee
Cisco Employee

From the port-channel summary I see the physical port is in "I" state.  This usually means the port is not receiving LACP packets from the other side.  (operationally individual).  To confirm this, check with "show lacp counters interface port-channel 10"  and look for sent but no receive counters incrementing every 30 seconds.  If this is the case, then this means the other end of this port-channel is not correctly configured for LACP.

Regards,

steveN

View solution in original post

4 Replies 4

Oleksandr Nesterov
Cisco Employee
Cisco Employee

Please add following outputs from your n5k devices:

sh log log | i 1/3

sh log log | i channel10

sh int eth 1/3

sh int po10

also please check physical connection and cable run. Such unexpected behavior very often caused by physical issues.

Regards

Alex

stanti
Cisco Employee
Cisco Employee

From the port-channel summary I see the physical port is in "I" state.  This usually means the port is not receiving LACP packets from the other side.  (operationally individual).  To confirm this, check with "show lacp counters interface port-channel 10"  and look for sent but no receive counters incrementing every 30 seconds.  If this is the case, then this means the other end of this port-channel is not correctly configured for LACP.

Regards,

steveN

Hey Steven, u seem to be on the right track here..

I reset the LACP counters for po10 and po20 which are the LACP channels back to node A and node B of our SAN.

NEX1# sh lacp counters interface port-channel 10

                    LACPDUs         Marker      Marker Response    LACPDUs

Port              Sent   Recv     Sent   Recv     Sent   Recv      Pkts Err

---------------------------------------------------------------------

port-channel10

Ethernet1/3        6      0        0      0        0      0        0

and then PO 20 looks good

NEX1# sh lacp counters interface port-channel 20

                    LACPDUs         Marker      Marker Response    LACPDUs

Port              Sent   Recv     Sent   Recv     Sent   Recv      Pkts Err

---------------------------------------------------------------------

port-channel20

Ethernet1/5        2      2        0      0        0      0        0

I'll fire this off the the storage guys as I know this was working.

Thanks for your help on this..

Cheers


Dave

Yes lacp counters is a great command to check if LACP is working or not. However, is there a possibility one end was configured as mode active and other end as mode on?

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