HP ProCurve 5300xl Series Management Manual page 44

Static Virtual LANs (VLANs)
VLAN Operating Rules
2-14
Adding or Deleting VLANs: Changing the number of VLANs supported
■
on the switch requires a reboot. (From the CLI, you must perform a write
memory command before rebooting.) Other VLAN configuration changes
are dynamic.
■ Inbound Tagged Packets: If a tagged packet arrives on a port that is not
a tagged member of the VLAN indicated by the packet's VID, the switch
drops the packet. Similarly, the switch will drop an inbound, tagged packet
if the receiving port is an untagged member of the VLAN indicated by the
packet's VID.
Untagged Packet Forwarding: To enable an inbound port to forward
■
an untagged packet, the port must be an untagged member of either a
protocol VLAN matching the packet's protocol or an untagged member of
a port-based VLAN. That is, when a port receives an incoming, untagged
packet, it processes the packet according to the following ordered crite­
ria:
a. If the port has no untagged VLAN memberships, the switch drops the
packet.
b. If the port has an untagged VLAN membership in a protocol VLAN
that matches the protocol type of the incoming packet, then the
switch forwards the packet on that VLAN.
c. If the port is a member of an untagged, port-based VLAN, the switch
forwards the packet to that VLAN. Otherwise, the switch drops the
packet.