S e n d d o c u m e n t a t i o n c o m m e n t s t o m d s f e e d b a c k - d o c @ c i s c o . c o m
52-9
Cisco MDS 9000 Family CLI Configuration Guide
OL-16184-01, Cisco MDS SAN-OS Release 3.x
Chapter 52 Monitoring Network Traffic Using SPAN
Configuring SPAN
To configure a SPAN filter, follow these steps:
To configure a span drop-threshold for a SPAN session, follow these steps::
Caution
By default, SPAN frames are dropped if the sum of the bandwidth of the source interfaces exceed the
bandwidth of the destination port. With a higher value, the SPAN traffic has a higher probability of
reaching the SPAN destination port instead of being dropped at the expense of data traffic throughput.
Caution
The span drop-threshold can be changed only if no span sessions are currently active on the switch.
Caution
By default, SPAN frames are dropped if the sum of the bandwidth of the source interfaces exceed the
bandwidth of the destination port. With a higher value, the SPAN traffic has a higher probability of
reaching the SPAN destination port instead of being dropped at the expense of data traffic throughput.
Caution
The span drop-threshold can be changed only if no span sessions are currently active on the switch.
Configuring SPAN for Generation 2 Fabric Switches
Cisco Generation 2 Fabric Switches (such as MDS 9124) support SPAN sessions in both directions, Rx
and Tx.
Note
While using Generation 2 Fabric Switches, you cannot create an additional active SPAN session when
you already have one.
The following example shows how to configure SPAN sessions for the ingress direction for this switch.
Command
Purpose
Step 1
switch#
config t
Enters configuration mode.
Step 2
switch(config)#
span session 1
switch(config-span)#
Configures the specified session (1).
Step 3
switch(config-span)#
source interface fc9/1 tx
Configures the source fc9/1 interface in the
egress (Tx) direction.
switch(config-span)#
source filter vsan 1-2
Configures VSANs 1 and 2 as session filters.
switch(config-span)#
source interface fc7/1 rx
Configures the source fc7/1 interface in the
ingress (Rx) direction.
Command
Purpose
Step 1
switch#
config t
Enters configuration mode.
Step 2
switch(config)#
span drop-threshold 15
switch(config-span)#
Configures the SPAN drop-threshold.