Allied Telesis C613-02013-00 Switch User Manual


 
Layer 2 Switching 47
Rapier Switch Software Release 2.2.1
C613-02013-00 Rev A
For each VLAN, the destination MAC address of a frame to be forwarded is
checked against the Forwarding Database. If there is no entry for the
destination address and VLAN, the frame is transmitted on all ports in the
VLAN that are in the ‘Forwarding’ or ‘Disabled’ states, except the port on
which the frame was received. This process is referred to as flooding. If an entry
is found in the Forwarding Database, but the entry is not marked as
‘Forwarding’ or the entry points to the same port the frame was received on,
the frame is discarded. Otherwise, the frame is transmitted on the port
specified by the entry in the Forwarding Database.
A dynamic entry is automatically deleted from the Forwarding Database when
its ageing timer expires.
The Egress Rules
Once the Forwarding Process has determined which ports and transmission
queues to forward a frame from, the Egress Rules for each port determine
whether or not the outgoing frame is VLAN-tagged with its numerical VLAN
Identifier (VID). (See “Virtual LANs” on page 35).
When a port is added to a VLAN, it is configured to transmit either untagged
or VLAN tagged packets, using the command:
ADD VLAN={vlanname|1..4094} PORT={port-list|ALL}
[FRAME={TAGGED|UNTAGGED}]
This setting can be changed for a port which is already part of a VLAN, using
the command:
SET VLAN={vlanname|1..4094} PORT={port-list|ALL}
FRAME={UNTAGGED|TAGGED}
Table 6: Parameters in the output of the SHOW SWITCH FILTER command
Parameter Meaning
Entry The number identifying the filter entry.
Destination Address The destination MAC address for the entry.
VLAN The VLAN name and identifier for the entry.
Port The outbound port to match for the filter entry to be applied.
Action The action specified by the filter entry; one of “Forward” or
“Discard”.
Source This parameter is either “static” (indicating the filter is a static
filter) or “learned” (indicating the filter is present either
because it has been added with the LEARN parameter of the
SET SWITCH PORT command, or has been dynamically learned
during normal intrusion detection operation).