Lenovo RackSwitch G8264 Application Manual page 164

If a port's native VLAN is a private VLAN and its allowed VLAN range contains
only invalid VLANs (either reserved VLANs or VLANs the port cannot belong to),
removing the private VLAN mapping from the port will add the port to default
VLAN and add the default VLAN to the allowed VLAN range.
When setting up multiple VLANs, ports configured in private VLAN mode are not
added to private VLANs unless the private VLANs are also configured for those
ports.
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G8264 Application Guide for ENOS 8.4