360 Monitoring Switch Traffic
The packet that is copied to the destination port is in the same format as the 
original packet on the wire. This means that if the mirror 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 being transmitted on the source 
port.
After you configure the port mirroring session, you can enable or disable the 
administrative mode of the session to start or stop the probe port from 
receiving mirrored traffic. 
Why is Traffic Monitoring Needed?
Monitoring the traffic that the switch handles, as well as monitoring all traffic 
in the network, can help provide information about network performance and 
utilization. This information can be useful in network planning and resource 
allocation. Information about traffic flows can also help troubleshoot 
problems in the network.
Default Traffic Monitoring Values
The sFlow agent is enabled by default, but sampling and polling are disabled 
on all ports. Additionally, no sFlow receivers (collectors) are configured. 
Table 16-1 contains additional default values for the sFlow feature.
RMON is enabled by default, but no RMON alarms, events, or history 
statistic groups are configured.
Port mirroring is disabled, and no ports are configured as source or destination 
ports. After you configure a port mirroring session, the administrative mode is 
disabled until you explicitly enable it.
Table 16-1. sFlow Defaults
Parameter Default Value
Receiver timeout for sampling 0
Receiver port 6343
Receiver Maximum Datagram Size 1400 bytes
Maximum header size 128 bytes