First off The Catalyst 2970, 3560, and 3750 Switches do not require the configuration of a reflector port when you configure an RSPAN session.
This is from the 3550 documentation: The reflector port is the mechanism that copies packets onto an RSPAN VLAN. The reflector port forwards only the traffic from the RSPAN source session with which it is affiliated. Any device connected to a port set as a reflector port loses connectivity until the RSPAN source session is disabled. The reflector port has these characteristics: •It is a port set to loopback. •It cannot be an EtherChannel group, it does not trunk, and it cannot do protocol filtering. •It can be a physical port that is assigned to an EtherChannel group, even if the EtherChannel group is specified as a SPAN source. The port is removed from the group while it is configured as a reflector port. •A port used as a reflector port cannot be a SPAN source or destination port, nor can a port be a reflector port for more than one session at a time. •It is invisible to all VLANs. •The native VLAN for looped-back traffic on a reflector port is the RSPAN VLAN. •The reflector port loops back untagged traffic to the switch. The traffic is then placed on the RSPAN VLAN and flooded to any trunk ports that carry the RSPAN VLAN. •Spanning tree is automatically disabled on a reflector port. If the bandwidth of the reflector port is not sufficient for the traffic volume from the corresponding source ports and VLANs, the excess packets are dropped. A 10/100 port reflects at 100 Mbps. A Gigabit port reflects at 1 Gbps. I'll probably get the wording wrong here, but it has to do with wether or not the switch has an asic to be able to rspan the traffic. The 3550 doesn't so you have to use a physical port. I'm pretty sure that I'm conveying that correctly but I'm sure someone will correct me if I didn't. Regards, Brandon Carroll - CCIE #23837 Senior Technical Instructor - IPexpert Mailto: [email protected] Telephone: +1.810.326.1444 Live Assistance, Please visit: www.ipexpert.com/chat eFax: +1.810.454.0130 IPexpert is a premier provider of Classroom and Self-Study Cisco CCNA (R&S, Voice & Security), CCNP, CCVP, CCSP and CCIE (R&S, Voice, Security & Service Provider) Certification Training with locations throughout the United States, Europe and Australia. Be sure to check out our online communities at www.ipexpert.com/communities and our public website at www.ipexpert.com. On Wed, Feb 17, 2010 at 6:36 AM, Kingsley Charles <[email protected]> wrote: > Hi all > > For IPS interface in Promisuous mode, we configure switch for monitor > session. When we use remote vlans, for the destination cmd, we have the > "reflector-port" at end end. > > monitor session 1 destination remote vlan 999 reflector-port > > > Can someone explain, what does this do? It is not optional. Which port > should be the reflector port? > > > > With regards > Kings > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com
