Advanced Traffic Management Guide K/KA/KB.15.15

VLAN port assignments Any ports not specifically removed from the default VLAN
remain in the DEFAULT_VLAN, regardless of other port
assignments. Also, a port must always be a tagged or
untagged member of at least one port-based VLAN.
Voice-Over-IP (VoIP) VoIP operates only over static, port-based VLANs.
Multiple VLAN types configured on
the same port
A port can simultaneously belong to both port-based and
protocol-based VLANs.
Protocol Capacity A protocol-based VLAN can include up to four protocol
types. In protocol VLANs using the IPv4 protocol, to support
normal IP network operation ARP must be one of these
protocol types (to support normal IP network operation).
Otherwise, IP traffic on the VLAN is disabled.
If you configure an IPv4 protocol VLAN that does not include
the ARP VLAN protocol, the switch displays the following
message which indicates a protocol VLAN configured with
IPv4 but not ARP:
HP Switch(config)#: vlan 97 protocol ipv4
IPv4 assigned without ARP, this may result in
undeliverable IP packets.
Deleting Static VLANs A VLAN can be deleted even if there are currently ports
belonging to it. The ports are moved to the default VLAN.
Adding or Deleting VLANs To Change the number of VLANs supported on the switch
requires a reboot.
NOTE: 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
criteria:
1. If the port has no untagged VLAN memberships, the
switch drops the packet.
2. 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.
3. 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.
Introducing tagged VLAN technology into networks running untagged VLANs 49