VLAN scaling guidelines for Full Switch mode Managing Fibre Channel Zones on MX9116n FSE Full Switch mode IO module replacement process VLAN stacking Dell Technologies introduces VLAN stacking in Dell SmartFabric OS10.5.4.0. This feature, commonly called Q-in-Q, is available for use on the Dell PowerEdge MX platform in Full Switch mode starting with version OS10.5.4.1.