Port Configuration

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3
Configuring Port Mirroring
You can mirror traffic from any source port to a
target port for real-time analysis. You can then
attach a logic analyzer or RMON probe to the
target port and study the traffic crossing the
source port in a completely unobtrusive manner.
Command Usage
• Monitor port speed sh ould match or exceed source port speed, otherwise traffic
may be dropped from the monitor port.
• All mirror sessions ha ve to share the same destination port.
• When mirroring p ort traffic, the target port must be included in the same VLAN as
the source port.
Command Attributes
•Mirror Sessions – Displays a list of current mirror sessions.
•Source Unit – The unit whose port traffic will be monitored.
•Source Port – The port whose traffic will be monitored.
•Type – Allows you to select which traffic to mirror to the target port, Rx (receive),
or Tx (transmit).
•Target Unit – The unit whose port will “duplicate” or “mirror” the traffic on the
source port.
•Target Port – The port that will mirror the traffic on the source port.
Web – Click Port, Mirror Port Configuration. Specify the source port/unit, the traffic
type to be mirrored, and the monitor port/unit, then click Add.
Figure 3-48. Mirror Port Configuration
CLI – Use the interface command to select the monitor port, then use the port
monitor command to specify the source port and traffic type.
Console(config)#interface ethernet 1/10 4-104
Console(config-if)#port monitor ethernet 1/13 tx 4-115
Console(config-if)#
Source
port(s)
Single
target
port