70 AT-8800 Series Switch User Guide
Software Release 2.6.1
C613-02039-00 REV A
the BCLIMIT parameter description for important information about packet
rate limiting. The default value for this parameter is NONE. If packet storm
protection limits are set on the switch, the PORT parameter must specify
complete processing blocks.
The ability of the switch to limit packet reception rates for different classes of packets is
dependent on the particular switch hardware. In particular, groups of ports may have to
have the same limits set, and the same limit may be set for the different types of packets,
depending on the hardware. Whenever packet rate limits are set on switches which have
this type of constraint, the latest parameter values entered will supersede earlier values.
When a command entered for specified ports changes the parameters for other ports, a
message will indicate these changes.
The SHOW SWITCH PORT command displays the packet storm protection
settings (Figure 12 on page 64).
SHOW SWITCH PORT=port-list
Port Mirroring
Port mirroring allows traffic being received and transmitted on a switch port to
be sent to another switch port, the mirror port, usually for the purposes of
capturing the data with a protocol analyser. This mirror port is the only switch
port which belongs to no VLANs, and therefore does not participate in any
other switching. Before the mirror port can be set, it must be removed from all
VLANs except the default VLAN. The port cannot be part of a trunk group.
To set the mirror port (and remove it from the default VLAN) use the
command:
SET SWITCH MIRROR={NONE|port}
If another port was previously set as the mirror port, this command returns the previous
mirror port to the default VLAN as an untagged port. Return this port to any VLANs
to which it should belong, using the ADD VLAN PORT command, or set it as a tagged
port using the SET VLAN PORT command if required.
Either traffic received on a port or traffic transmitted by the port, or both, can
be mirrored. This setting and the source port(s) from which traffic is sent to the
mirror port are specified using the command:
SET SWITCH PORT={port-list|ALL} MIRROR={NONE|RX|TX|BOTH}
Mirroring four or more ports may significantly reduce switch performance.
The MIRROR parameter specifies the role of these port(s) as a source of mirror
traffic. If NONE is specified, no traffic received or sent on these port(s) will be
mirrored. If RX is specified, all traffic received on these port(s) will be mirrored.
If TX is specified, all traffic transmitted on these port(s) will be mirrored. If
BOTH is specified, all traffic received and transmitted will be mirrored. Traffic
will actually only be mirrored if there is a mirror port defined and if mirroring
is enabled. The default is NONE.