Port Monitoring | 69132Port MonitoringPort Monitoring is supported on platforms: e c s zPort Monitoring, also known as Port Mirroring, is a feature that copies all incoming or outgoing packets onone port and forwards (mirrors) them to another port. The source port is the monitored port (MD) and thedestination port is the monitoring port (MG). Port Monitoring functionality is different between platforms,but the behavior is the same, with highlighted exceptions.This chapter is divided into the following sections:• Important Points to Remember on page 691• Port Monitoring on E-Series on page 692• Port Monitoring on C-Series, S-Series, and Z-Series on page 693• Configuring Port Monitoring on page 696• Flow-based Monitoring on page 698Important Points to Remember• Port Monitoring is supported on physical ports only; VLAN and port-channel interfaces do not supportport monitoring.• A SONET port may only be a monitored port.• The Monitored (source, “MD”) and Monitoring ports (destination, “MG”) must be on the same switch.• In general, a monitoring port should have no ip address and no shutdown as the only configuration;FTOS permits a limited set of commands for monitoring ports; display them using the command ?. Amonitoring port also may not be a member of a VLAN.• There may only be one destination port in a monitoring session.• A source port (MD) can only be monitored by one destination port (MG). The following error isdisplayed if you try to assign a monitored port to more than one monitoring port.FTOS(conf)#mon ses 1FTOS(conf-mon-sess-1)#$gig 0/0 destination gig 0/60 direction bothFTOS(conf-mon-sess-1)#do show mon sesSessionID Source Destination Direction Mode Type--------- ------ ----------- --------- ---- ----1 Gi 0/0 Gi 0/60 both interface Port-basedFTOS(conf-mon-sess-1)#mon ses 2FTOS(conf-mon-sess-2)#source gig 0/0 destination gig 0/61 direction both% Error: MD port is already being monitored.
