| Port Mirroring Commands
Local Port Mirroring Commands
both - Mirror both received and transmitted packets.
vlan-id - VLAN ID (Range: 1-4093)
mac-address - MAC address in the form of xx-xx-xx-xx-xx-xx or
No mirror session is defined.
When enabled for an interface, default mirroring is for both received and
When enabled for a VLAN or a MAC address, mirroring is restricted to received
Interface Configuration (Ethernet, destination port)
You can mirror traffic from any source port or trunk to a destination port for
real-time analysis. You can then attach a logic analyzer or RMON probe to the
destination port and study the traffic crossing the source port or trunk in a
completely unobtrusive manner.
Set the destination port by specifying an Ethernet interface with the
configuration command, and then use the port monitor command to specify
the source of the traffic to mirror. Note that the destination port cannot be a
trunk or trunk member port.
When mirroring traffic from a port or trunk, the mirror port/trunk and monitor
port speeds should match, otherwise traffic may be dropped from the monitor
port. When mirroring traffic from a VLAN, traffic may also be dropped under
When VLAN mirroring and port or trunk mirroring are both enabled, the target
port can receive a mirrored packet twice; once from the source mirror port or
trunk and again from the source mirror VLAN.
When mirroring traffic from a MAC address, ingress traffic with the specified
source address entering any port in the switch, other than the target port, will
be mirrored to the destination port.
When traffic matches the rules for both port mirroring, and for mirroring of
VLAN traffic or packets based on a MAC address, the matching packets will not
be sent to target port specified for port mirroring.
Spanning Tree BPDU packets are not mirrored to the target port.
You can create multiple mirror sessions, but all sessions must share the same
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