Symptoms:
When attempting to migrate a virtual machine from one vSphere Distributed Switch (vDS) to another, you experience these symptoms:

• The migration fails.
• You see these errors in the vSphere Web Client similar to:
  
  The target host doesn’t support the virtual machines current hardware requirements. The destination virtual switch version or type (VDS 7.0.0) is different than the minimum required version or type (VDS 6.6.0) necessary to migrate VM from source virtual switch.

VMware vSphere 6.7.x
VMware vSphere 6.5.x
VMware vSphere 7.0.x

This issue occurs because there are comparisons being made between the vDS on the source and destination ESXi Hosts/vCenter for the vMotion operation.

The vDS versions must match!

A live migration (a.k.a. Hot Migration) between DVS/vDS versions, is NOT recommended.

This is an expected behavior when migrating between mixed vSphere Distributed Switches.

To resolve this issue:

• upgrade the vDS with the lower version to match that of the higher one, if possible.
• Alternatively, power-off the VM and then do the migration (cold migration).

Note: The workaround should only be used for the vMotion between different DVS versions for migrations between on-prem and VMware Cloud. If the below workaround is applied to hot-migrate a VM between vDS/DVS versions, the VM may lose network connectivity.

Workaround:
To work around this issue:

vCenter Server 6.5.x and vCenter Server 6.7.x

1. Log in to the vCenter Server using the HTML5 or vSphere Web Client.
2. Highlight your vCenter Server name in the left-hand column and then click on the Configure tab on the right.
3. Go to Advanced Settings and click Edit Settings.
4. At the bottom of the pop-up window, add the following property in the Name section:
   
   config.migrate.test.NetworksCompatibleOption.AllowMismatchedDVSwitchConfig
    
5. Set the value to true.
6. Click Add.
7. Click Save.
8. Re-try the migration.

vCenter Server 7.0.x and later

1. Log in to the vCenter Server using the HTML5 or vSphere Web Client.
2. Highlight your vCenter Server name in the left-hand column and then click on the Configure tab on the right.
3. Go to Advanced Settings and click Edit Settings.
4. At the bottom of the pop-up window, add the following property in the Name section: 
   
   config.vmprov.enableHybridMode
    
5. Set the value to true.
6. Click Add.
7. Click Save.
8. Re-try the migration.

Note: For enabling hybrid mode in vCenter, the target DVS version must be at least 6.0.0.

Note: The workaround should only be used for the vMotion between different DVS versions for migrations between on-prem and VMware Cloud. If the below workaround is applied to hot-migrate a VM between vDS/DVS versions, the VM may lose network connectivity.

Note: At this time, the workaround does not work if the source vDS is version 7.0.3.

config.vmprov.enableHybridMode = false (default setting)

	Destination vDS version
Source vDS version	6.5.0	6.6.0	7.0.0	7.0.2	7.0.3
6.5.0	✅	❌	❌	❌	❌
6.6.0	❌	✅	❌	❌	❌
7.0.0	❌	❌	✅	❌	❌
7.0.2	❌	❌	❌	✅	❌
7.0.3	❌	❌	❌	❌	✅

config.vmprov.enableHybridMode = true (workaround applied)

	Destination vDS version
Source vDS version	6.5.0	6.6.0	7.0.0	7.0.2	7.0.3
6.5.0	✅	✅	✅	✅	✅
6.6.0	✅	✅	✅	✅	✅
7.0.0	✅	✅	✅	✅	✅
7.0.2	✅	✅	✅	✅	✅
7.0.3	❌	❌	❌	❌	✅

Understand vMotion networking requirements (59232)
Blog: Hot and Cold Migrations; Which Network is Used?

Impact/Risks:
Migration of the virtual machine would fail, resulting in the error above.

Note: If the below workaround is applied to hot-migrate a VM between vDS/DVS versions, the VM may lose network connectivity.