VM connectivity issue

[mhasabal]

Happy 4th everyone

Please help me out to understand the no connectivity issue i am experiencing for one of the VMs "V1"

please see attached text config file

interface Vethernet7

  inherit port-profile data_vlan172

  description V1, Network Adapter 1

  vmware dvport 512

port-profile type ethernet vm-data-uplink

  vmware port-group

  switchport mode trunk

  switchport trunk allowed vlan 4,172

  no shutdown

  system vlan 4,172

  state enabled

port-profile type vethernet data_vlan172

  vmware port-group

  switchport mode access

  switchport access vlan 172

  no shutdown

  system vlan 172

  state enabled

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

N1000vUCS# sh vlan

VLAN Name                             Status    Ports

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

1    default                          active    Eth3/2, Eth4/4, Eth5/2

4    MGMT_VMWARE1000V                 active    Veth1, Veth2, Veth3, Veth4

                                                Veth5, Veth6, Veth8, Veth9

                                                Veth10, Veth11

120  CONTROL_UCS                      active   

130  PACKET_UCS                       active   

172  VLAN0172                         active    Veth7

VLAN Type

---- -----

1    enet 

4    enet 

120  enet 

130  enet 

172  enet 

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

i am not able to ping the default GW 172.20.1.254

currently the VM has static IP 172.20.1.35/24

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

N1000vUCS# sh ip arp vethernet 7

IP ARP Table

Total number of entries: 0

Address         Age       MAC Address     Interface

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

N1000vUCS# sh ip arp summary

IP ARP Table - Adjacency Summary

  Resolved   : 0

  Incomplete : 0

  Unknown    : 0

  Total      : 0

[abbharga]

Hi,

Looking at the outputs, is this N1K running on a UCS system?

If so can you verify if you have defined vlan 172 on the UCS system and also attached it to the vmnic under the service profile? Also if its native vlan on the UCS vmnic you will have to mark it as native on the uplink port-profile.

./Abhinav

[mhasabal]

abbharga

thanks for the reply.

vlan 172 is not defined on the UCS, but from the n1k i am able to hit the 4500 core sw

[abbharga]

you will have to define the vlan 172 on the UCS. Can you explain more on what you mean by hitting the 4500 from the n1k?

[mhasabal]

i am able to ping the gw 172.20.1.254 from the n1k

[mhasabal]

i was able to define vlan 172 from the LAN tab for both fabrics A & B when adding the vlan on the service profile it shows an overlap

[abbharga]

The ping from the N1k to the GW IP is via the mgmt0 interface, where as the traffic for the VM on vlan 172 will be carried on the uplink interfaces from the blade to the 6120 and up north, for this you need to define the vlan 172 on the UCS, add it to the vmnic (which will trunk the interface from the 6120 to the blade) and automatically add / trunk the vlan on the uplink interface on the 6120.

You need not define the vlans individually on the FI-A & FI-B, whie creating the vlan you can configure it as a global vlan which will define it on both the FI.

./Abhinav

[sean.wang]

If your configurations are correct, and if your ping is not even working without going through any routing hops, check if you have hit a bug that causes VM connectivity and ARP issue. I have posted details below, interested in if there are other Nexus 1000v users hitting the same bug.

http://www.seanxwang.com/2010/07/nexus1000v-bug-widespread-vm.html

[Robert Burns]

@Sean - Are you referring to CSCte96034 "MAC move packet must be sent to broadcast address" ?  This bug was causing MAC move notifications to be discarded based on the destination address being used.

This bug has been fixed in the latest release 4.0.4.SV1.3.  Information on this bug can be found in the bug toolkit -> http://tools.cisco.com/Support/BugToolKit/search/getBugDetails.do?method=fetchBugDetails&bugId=CSCte96034

If this isn't one you're referring to let me know the bug ID if you have it and I'll see if I can provide any further details.

Robert

[sean.wang]

Robert, it's a different bug, CSCtg72137. Thanks.

[Robert Burns]

That will be fixed in the upcoming maintenance release 4.0(4)SV1(3a) due out next week.

Robert

[sean.wang]

Yes, got an early trial, and confirmed the fix.

It was a particularly nasty bug that all users should be warned, given its impact, and difficulty tracking down.

4.0(4)SV1(3a) fixed a number of bugs, and should be upgraded to immediately.