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1000v VXLAN Can't get uplink MTU: 4681

I'm trying to configure VXLAN on 1000v but it not working between two esx.

As I followed the troubleshooting guide on Cisco's website I discovered the following error:  Can't get uplink MTU: 4681

Here is the output of the "vemcmd show vxlan-stats ltl 50"  command. Port LTL 50 is the VM's port.

vemcmd show vxlan-stats ltl 50

VXLAN Port Stats for LTL 50

Unicast Encapsulations: 0

Multicast Encapsulations: 0

Unicast Decapsulations: 0

Multicast Decapsulations: 0

IP Pre-fragmentations: 0

TSO Processed Packets: 0

ICMP Pkt Too Big msgs from upstream: 0

ICMP Pkt Too Big msgs sent to VM: 0

Drop Statistics:

MTU Exceeded: 0

Generic Encap Fail: 0

No VMKNIC for Encap: 0

ARP Miss for Encap IP: 0

VXLAN BD Error: 0

Can't map packet: 0

Generic Decap Fail: 0

Encap source IP is one of ours: 0

Segment BD Error: 0

Dest Mcast IP not Segment Group IP: 0

Mcast Pkt for non-0th VXLAN Interface: 0

Pinning Failed on Decap: 0

Can't get uplink MTU: 4681

TSO Processing Failure: 0

PreFrag Processing Failure: 0

If I run esxcfg-vswitch -l I get this (strange thing is I've set mtu to 9000 on 1000v):

DVS Name         Num Ports   Used Ports  Configured Ports  MTU     Uplinks

Nexus_1000v      256         14          256               1500    vmnic0

  DVPort ID           In Use      Client

  96                  1           vmnic0

  97                  0

  98                  0

  99                  0

  100                 0

  101                 0

  102                 0

  103                 0

  104                 0

  105                 0

  106                 0

  107                 0

  108                 0

  109                 0

  110                 0

  111                 0

  112                 0

  113                 0

  114                 0

  115                 0

  116                 0

  117                 0

  118                 0

  119                 0

  120                 0

  121                 0

  122                 0

  123                 0

  124                 0

  125                 0

  126                 0

  127                 0

  161                 1           vmk1

  192                 1           VXLAN 1 ESX12.eth0

I've set mtu to 9000 on the UPLINK profile (port-profile)  and enabled  jumbo frames support on the upstream switch.

Here is the output of show run: http://pastebin.com/6X0EhQsD

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New Member

1000v VXLAN Can't get uplink MTU: 4681

Some updates. I debugged VEMs a little and I found this:

Sep  4 13:19:02.326602       141  10    1  64  Packet sf_vnseg_local_ports_in_flood: ltl 50 source_ltl 50

Sep  4 13:19:02.326603       142  10    1  64  Packet sf_vnsegment_encap_prep: No local ports for flooding

Sep  4 13:19:02.326607       143  10    1  1  Error sf_lisp_getmtu: No port entry for ltl 0

Sep  4 13:19:02.326616       144  10    1  64  Packet sf_vnsegment_encap_prep: Can't get MTU for LTL 0 - drop - no local rcvrs

Sep  4 13:19:07.085070       145   8    1  64  Packet sf_vnsegment_encap_prep: Packet from LTL 50 for encap

Sep  4 13:19:07.085077       146   8    1  64  Packet sf_vnsegment_encap_prep: For inner SMAC 00:50:56:aa:6e:eb: ENCAP: LTL 49 VLAN 2004

Sep  4 13:19:07.085080       147   8    1  64  Packet sf_vnsegment_encap_prep: Mcast Encap: SIP 10.255.255.13 SMAC 00:50:56:74:7a:b7

Sep  4 13:19:07.085082       148   8    1  64  Packet sf_vnseg_local_ports_in_flood: ltl 50 source_ltl 50

It seems LTL 0 is missing but I've no idea what is LTL 0.

Anyone have an idea?

PS.:

~ # vemcmd show port

  LTL   VSM Port  Admin Link  State  PC-LTL  SGID  Vem Port  Type

   17     Eth4/1     UP   UP    FWD       0          vmnic0

   49      Veth1     UP   UP    FWD       0            vmk1  VXLAN

   50      Veth3     UP   UP    FWD       0        VXLAN 1 ESX12.eth0

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