During vSphere 4.x to 5.x updates I occasionally run into the situation where dvSwitches are used on the current vCenter4  and the customer wants to install a fresh copy of vCenter5 (with a new dvSwitch).

Within this article I will describe a minimum downtime (1 ping-loss or less) procedure to cover this, guided by pictures to get a clear understanding.

Step 1 – Starting point
First of all we got the ESXi Host and VM’s connected to the dvSwitch.

 

Migrate to new vCenter Server while using dvSwitches_vmware

 

Step 2
Create a new vSwitch and add virtual machine portgroups to it with the same VLAN’s that are available on the dvSwitch. Add “local” to the naming convention to ensure easy identification.

 

Migrate to new vCenter Server while using dvSwitches_vmware_02

 

Step 3
Detach one of the vmnic’s from the dvSwitch and add it to the newly created vSwitch. This ensures the same network connectivity on the vSwitch as on the dvSwitch (assuming network is configured as it supposed to be.)

Note:

  1. Ensure that load balancing is active on the dvSwitch (no standby vmnics) before detaching one of the vmnics.
  2. Detaching one vmnic from the dvSwitch basically means interrupting possible the network traffic. It’s recommended to first do this on an ESXi Host with some test VM’s (or less critical VM’s) to measure possible ping-loss. The environments I migrated all lost either no or a maximum of 1 ping, which was acceptable for the customer.

 

Migrate to new vCenter Server while using dvSwitches_vmware_03

 

Step 4
Change the VM’s portgroup to the corresponding new “local” portgroup you created on the vSwitch (within step 2).
This can be done either manually or via the “Migrate Virtual Machine Networking” wizard within the dvSwitch.

Note:

  1. Changing the portgroup of a VM  basically means interrupting  the network traffic. It’s recommended to first try this on some test VM’s (or less critical VM’s)  to measure possible ping-loss. The environments I migrated all lost either no or a maximum of 1 ping, which was acceptable for the customer.

 

Migrate to new vCenter Server while using dvSwitches_vmware_04

 

Step 5
Detach the remaining vmnic from the dvSwitch (the dvSwitch will not have any uplinks anymore at this time).

 

Migrate to new vCenter Server while using dvSwitches_vmware_05

 

Step 6
Delete the ESXi Host from the dvSwitch configuration.

 

Migrate to new vCenter Server while using dvSwitches_vmware_06

 

From this point on all VM’s are moved towards the vSwitch and the ESXi Host is disconnected from the dvSwitch, which means that it can easily be moved over to the new vCenter5 server.
This process can be reversed to get the VM’s back on the new dvSwitch within vCenter5.