This document provides a sample configuration and verification for the
Switched Port Analyzer (SPAN) on the Cisco Nexus 7000 series devices to monitor
the traffic between Ethernet ports.
Ensure that you meet these requirements before you attempt this
The information in this document is based on the Nexus 7000 Series
The information in this document was created from the device in a
specific lab environment. All of the devices used in this document started with
a cleared (default) configuration. If your network is live, make sure that you
understand the potential impact of any command.
Refer to the
Technical Tips Conventions for more information on document
SPAN for ethernet ports monitor all traffic for source port, which
sends a copy of the traffic to a destination port. The network analyzer, which
is attached with destination port, analyzes the traffic that passes through
Source port can be a single port or multiple ports or a VLAN, which is
also called a monitored port. You can monitor all the packets for source port
which is received (ingress), transmitted (egress), or bidirectional (both). A
replication of the packets is sent to the destination port for
For VLAN-based SPAN (VSPAN), all ports in VLAN are source ports. So the
traffic in the VLAN is monitored. You can apply VLAN based filter on trunk port
of the switch to limit SPAN traffic monitor.
The destination port is a port that was connected to the device such as
SwitchProbe device or other Remote Monitoring (RMON) probe or security device
that can receive and analyze the copied packets from single or multiple source
Switch supports multiple SPAN sessions (up to 48 sessions), but only
two sessions can be run simultaneously and others are shutdown. A port of the
switch is configured as either the source port or the destination port.
Note: Span may use the same replication engine as multicast on the module
and there is a physical limit to the amount of replication that each
replication engine can do. Nexus 7000 modules have multiple replication engines
for each module and under normal circumstances, multicast is unaffected by a
span session. But it is possible to impact multicast replication if you have a
large number of high rate multicast streams inbound to the module, and the port
you monitor uses the same replication engine.
In this section, you are presented with the information to configure
single SPAN session on Nexus 7000 Series Switch. In this example, the switch
interface ethernet 3/11 has been configured as the source port and the
interface ethernet 3/48 has been configured as the destination port.
In this configuration example, Step 1 shows you how to configure the
destination port and Step 2 shows you how to configure a SPAN session.
Note: Use the
Command Lookup Tool
(registered customers only)
to obtain more information on
the commands used in this section.
This document uses these configurations:
Destination port configuration
switch7000-1(config)#interface ethernet 3/48
!--- Configures the switchport parameters for a port.
!--- Configures the switchport interface as a SPAN destination.
SPAN session configuration
switch7000-1(config)#monitor session 1
!---Configure the source port with traffic direction.
switch7000-1(config-monitor)#source interface ethernet 3/11 both
!--- Configure the destination port.
switch7000-1(config-monitor)#destination interface ethernet 3/48
!--- To enable the SPAN session, by default session in shutdown state.
!--- To save the configurations in the device.
switch7000-1(config)#copy running-config startup-config
Use this section to confirm that your configuration works
Output Interpreter Tool
(registered customers only)
(OIT) supports certain
show commands. Use the OIT to view an analysis of
show command output.
command gives the status of the SPAN
Session State Reason Description
------- ----------- ----------------------
1 up The session is up
monitor session all
command gives a summary of the current
switch7000-1#show monitor session all
type : local
state : up
source intf :
rx : Eth3/11
tx : Eth3/11
both : Eth3/11
source VLANs :
filter VLANs : filter not specified
destination ports : Eth3/48
From these commands you can verify the SPAN configuration on the Nexus
7000 Series Switches.