4

In ESXi, how does one move an existing port group to a different vSwitch?

This appears to be an often-desired action, but with no readily-accessible solution:

enter image description here

So, I have one large vSwitch with about 8 different port groups (each with 4-6 VMs assigned). Due to network changes, I need to break this vSwitch up into multiple vSwitches (each with its own physical adapter). I want to simply move the existing port groups (including VLAN IDs) to the correct (new) vSwitch.

Is there an easy way to do this without reconfiguring the entire thing? If there were some XML file where this is stored, it would be a 5-second cut & paste operation.

Jonathon Reinhart
  • 3,514

1 Answers1

4

Disclaimer: This is certainly not a supported/recommended way of doing this. Don't do it on a production box. I did it with all VMs powered off, and vSphere disconnected, just to be safe.

First, you need to access the ESXi console. Then, this can easily be done by editing /etc/vmware/esx.conf.

For each vSwitch, there is an entry like:

/net/vswitch/child[0000]/name = "vSwitch0"
/net/vswitch/child[0000]/...
/net/vswitch/child[0001]/name = "vSwitch1"
/net/vswitch/child[0001]/...
...

You can rename vSwitches there, by the way.

The port groups are nodes under the vSwitches:

/net/vswitch/child[0000]/portgroup/child[0000]/name = "Management Network"
/net/vswitch/child[0000]/portgroup/child[0000]/...
...
/net/vswitch/child[0000]/portgroup/child[0001]/name = "VM Network"
/net/vswitch/child[0000]/portgroup/child[0001]/...
...

To move a port group from one vSwitch to another, you simply change which /net/vswitch/child[XXXX]/ node it is under, making sure to respect what portgroup children are already there. In other words, once you move a port group to another vSwitch, you might need to change its child number.

Note: You have to re-number all of the relevant lines (all of the lines that correspond to that port group).

Note 2: If there are teamPolicy entries present for a port group, you may need to ensure that the associated uplinks[nnnn]/pnic = settings match the actual vmnicN for the vswitch that you're moving it to.

After editing the file, I simply rebooted the ESXi server: $ reboot. There may be some service or process that could be restarted instead, but I figured rebooting was the easiest and safest way.

Example

Say we have two vSwitches each with a single vmnic uplink, and two port groups:

vSwitch0        --> vmnic0
|--portGroupA
|--portGroupB

vSwitch1        --> vmnic1
|--portGroupC
|--portGroupD

The relevant entries in esx.conf might look something like this1:

# vSwitch0
/net/vswitch/child[0000]/...
/net/vswitch/child[0000]/name = "vSwitch0"
/net/vswitch/child[0000]/numPorts = "128"
# vSwitch0->portGroupA
/net/vswitch/child[0000]/portgroup/child[0000]/name = "portGroupA"
/net/vswitch/child[0000]/portgroup/child[0000]/teamPolicy/uplinks[0000]/pnic = "vmnic0"
# vSwitch0->portGroupB
/net/vswitch/child[0000]/portgroup/child[0001]/name = "portGroupB"
/net/vswitch/child[0000]/portgroup/child[0001]/teamPolicy/uplinks[0000]/pnic = "vmnic0"
/net/vswitch/child[0000]/uplinks/child[0000]/pnic = "vmnic0"

# vSwitch1
/net/vswitch/child[0001]/...
/net/vswitch/child[0001]/name = "vSwitch1"
/net/vswitch/child[0001]/numPorts = "128"
# vSwitch1->portGroupC
/net/vswitch/child[0001]/portgroup/child[0000]/name = "portGroupC"
/net/vswitch/child[0001]/portgroup/child[0000]/teamPolicy/uplinks[0000]/pnic = "vmnic1"
# vSwitch1->portGroupD
/net/vswitch/child[0001]/portgroup/child[0001]/name = "portGroupD"
/net/vswitch/child[0001]/portgroup/child[0001]/teamPolicy/uplinks[0000]/pnic = "vmnic1"
/net/vswitch/child[0001]/uplinks/child[0000]/pnic = "vmnic1"

Now, we want to move portGroupC from vSwitch1 to vSwitch0, so the configuration is like this:

vSwitch0        --> vmnic0
|--portGroupA
|--portGroupB
|--portGroupC

vSwitch1        --> vmnic1
|--portGroupD

To do this, we:

  1. Identify all of the portGroupC lines, which start with /net/vswitch/child[0001]/portgroup/child[0000]. Move those entries up with the vSwitch0 config (not necessary, but makes things clearer when editing).
  2. Change /net/vswitch/child[0001] to /net/vswitch/child[0000] on each line (because we're moving it to that switch).
  3. Realize that there is already a /net/vswitch/child[0000]/portgroup/child[0000] (portGroupA), and change portGroupC to /portgroup/child[0002].
  4. Realize that our uplink for that port group is now incorrect (if specified), and change uplinks[0000]/pnic = from vmnic1 to vmnic0 (because that is the vmnic serving that vSwitch.)

The final config should look like this:

# vSwitch0
/net/vswitch/child[0000]/...
/net/vswitch/child[0000]/name = "vSwitch0"
/net/vswitch/child[0000]/numPorts = "128"
# vSwitch0->portGroupA
/net/vswitch/child[0000]/portgroup/child[0000]/name = "portGroupA"
/net/vswitch/child[0000]/portgroup/child[0000]/teamPolicy/uplinks[0000]/pnic = "vmnic0"
# vSwitch0->portGroupB
/net/vswitch/child[0000]/portgroup/child[0001]/name = "portGroupB"
/net/vswitch/child[0000]/portgroup/child[0001]/teamPolicy/uplinks[0000]/pnic = "vmnic0"
# vSwitch1->portGroupC
/net/vswitch/child[0000]/portgroup/child[0002]/name = "portGroupC"
/net/vswitch/child[0000]/portgroup/child[0002]/teamPolicy/uplinks[0000]/pnic = "vmnic0"
/net/vswitch/child[0000]/uplinks/child[0000]/pnic = "vmnic0"

# vSwitch1
/net/vswitch/child[0001]/...
/net/vswitch/child[0001]/name = "vSwitch1"
/net/vswitch/child[0001]/numPorts = "128"
# vSwitch1->portGroupD
/net/vswitch/child[0001]/portgroup/child[0000]/name = "portGroupD"
/net/vswitch/child[0001]/portgroup/child[0000]/teamPolicy/uplinks[0000]/pnic = "vmnic1"
/net/vswitch/child[0001]/uplinks/child[0000]/pnic = "vmnic1"

Notice that I also changed portGroupD from portgroup/child[0001] to [0000] (as there was no longer a 0 entry.)

1 - The # comments are just for explanation here; I don't know if they work in the real file, and get blown away upon next configuration anyway.

Jonathon Reinhart
  • 3,514