Cisco Nexus 3548 - Prerequisites for ERSPAN; Guidelines and Limitations for ERSPAN

License RequirementProduct
ERSPAN requires no license. Any feature not
included in a license package is bundled with the
Cisco NX-OS system images and is provided at no
extra charge to you. For a complete explanation of
the Cisco NX-OS licensing scheme, see the License
and Copyright Information for Cisco NX-OS Software
available at the following URL: http://
www.cisco.com/en/US/docs/switches/datacenter/sw/
4_0/nx-os/license_agreement/nx-ossw_lisns.html.
Cisco NX-OS
Prerequisites for ERSPAN
ERSPAN has the following prerequisite:
•You must first configure the Ethernet interfaces for ports on each device to support the desired ERSPAN
configuration. For more information, see the Interfaces configuration guide for your platform.
Guidelines and Limitations for ERSPAN
ERSPAN has the following configuration guidelines and limitations:
•
ERSPAN supports the following:
◦
ERSPAN source session type (Packets are encapsulated as GRE-tunnel packets and sent on the IP
network.)
◦
ERSPAN destination session type (Support for decapsulating the ERSPAN packet is available.
The encapsulated packet is decapsulated at the destination box and the plain decapsulated packet
is spanned to a front panel port at the ERSPAN terminating point.)
•
ERSPAN source sessions are shared with local SPAN sessions. You can configure a maximum of eight
ERSPAN source or SPAN source sessions in a single direction; If both receive and transmit sources are
configured in the same session, it counts as two sessions and you can configure four such bidirectional
sessions at one time.
•
If you install NX-OS 5.0(3)U2(2), configure ERSPAN, and then downgrade to a lower version of
software, the ERSPAN configuration is lost. This situation occurs because ERSPAN is not supported
in versions before NX-OS 5.0(3)U2(2).
For information about a similar SPAN limitation, see Guidelines and Limitations for SPAN.
•
ERSPAN is not supported for packets generated by the supervisor.
•
ERSPAN sessions are terminated identically at the destination router.
•
ERSPAN is not supported for management ports.
•
A destination port can be configured in only one ERSPAN session at a time.
•
You cannot configure a port as both a source and destination port.
Cisco Nexus 3548 Switch NX-OS System Management Configuration Guide, Release 6.x
162
Configuring ERSPAN
Prerequisites for ERSPAN