ESXI 5.1 - Unable to trunk to cisco switch

Question

I have configured my esxi host vSwitch1 to use the secondary NIC on my VMware host.

On vSwitch1 configuration I have set the VLAN to 4095 which specifies to allow all VLANs.

If my cisco switch port configuration is set to an access port my server can ping the vlan interface on the switch.

If my cisco switch port configuration is set to a trunk, whilst it stays UP UP and CDP information is available, I lose my ping from VMware VM server to the local vlan interface on the switch and I lose any server connectivity to my network.

• Switch NIC teaming policy to Route based on originating virtual port ID

• Configuration based on: http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1006628

  interface GigabitEthernet0/42
  description Host Port
  switchport trunk encapsulation dot1q
  switchport trunk allowed vlan 18,220
  switchport mode trunk
  switchport nonegotiate
  spanning-tree portfast trunk
  end
  
  

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Output from ESXI CLI esxcfg-vswitch -l:

~ # esxcfg-vswitch -l
Switch Name Num Ports Used Ports Configured Ports MTU Uplinks
vSwitch0 128 5 128 1500 vmnic0

PortGroup Name VLAN ID Used Ports Uplinks
VM Network 4095 1 vmnic0
Management Network 4095 1 vmnic0

Switch Name Num Ports Used Ports Configured Ports MTU Uplinks
vSwitch1 128 4 128 1500 vmnic1

PortGroup Name VLAN ID Used Ports Uplinks
VM Network 2 4095 1 vmnic1

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Any tips welcome!!!

Solution

Instead of allowing all VLANs across you could setup a Port Group on your vSwitch for each VLAN, specifying the actual VLAN id in each. Then set your VMs NIC(s) to use the Port Group for it's subnet. You can do this by adding a Virtual Machine Network under the properties of your vSwitch.

Or You can set the VLAN ID in the NIC settings of your VM.

The problem you have in your current config, is that you are trunking two VLAN IDs (18 & 220) over to the vSwitch, and telling the vSwitch to pass all VLANs. However, your vSwitch is leaving the 802.1q tag on the traffic. In this config your VM would be expected to be aware of what VLAN id it's traffic is using.

Comments

[Lance]

AHA! I thought that setting it to 4095 was kind of like telling it it to trunk and let all things through, somewhat like telling to trunk without pruning... I have setup individual port groups for each vlan on my vSwitch0, cisco end set to trunk and it's working.

[Lance]

Are you able to tell me under what circumstances that you use the vlan 4095 option then? The KB is pretty unclear on this :|

[HostBits]

You would do this if you wanted your Server's NIC to handle the VLAN ID instead of the switch. Also, if the answer helped, please select it as the accepted answer. Hope this helps.

[Lance]

Having another problem you might be able to help with also: serverfault.com/questions/518934/…