Administrator Guide

524 Monitoring Switch Traffic
entries are purged); and do not utilize any static filter configuration. The
original configuration of a destination port is restored when the port is no
longer configured as a destination port.
Each source port can be configured whether to mirror ingress traffic (traffic
the port receives, or RX), egress traffic (traffic the port sends, or TX), or both
ingress and egress traffic.
The packet that is copied to the destination port is normally in the same
format as the original packet on the wire, except as noted in the following
section: Port Mirroring Behaviors. This means that if the mirror port is
copying a received packet, the copied packet is VLAN tagged or untagged as it
was received on the source port. If the mirror is copying a transmitted packet,
the copied packet is VLAN tagged or untagged as it is transmitted on the
source port. Destinations include physical interfaces and RSPAN VLANs.
After configuring the port mirroring session, enable or disable the
administrative mode of the session to start or stop the probe port from
receiving mirrored traffic.
Port Mirroring Behaviors
The following behaviors are applicable to monitor ports:
• The following source port types may be configured in more than one
session in support of M:N mirroring:
–Physical ports
–LAGs
–CPU
VLANs and RSPAN may not be configured as mirroring sources in more
than a single session.
NOTE: A DiffServ policy class definition or an ACL can be created that mirrors
specific types of traffic to a destination port. For more information, see
"Differentiated Services " on page 1445 or "Access Control Lists " on page 629.