Configuration restrictions and guidelines
When you configure an 802.1X critical VLAN, follow these restrictions and guidelines:
Assign different IDs to the voice VLAN, the PVID, and the 802.1X critical VLAN on a port. The assignment makes sure the port can correctly process VLAN-tagged incoming traffic.
You can configure only one 802.1X critical VLAN on a port. The 802.1X critical VLANs on different ports can be different.
You cannot specify a VLAN as both a super VLAN and an 802.1X critical VLAN. For information about super VLANs, see Layer 2—LAN Switching Configuration Guide.