Specifications

2-483
Catalyst 4500 Se ries S wit ch C is co IO S C om mand R efer ence —Re lease I OS XE 3 .3.0 XO(1 5.1 (1)XO)
OL_28738 -01
Chapter 2 Cisco IOS Commands for the Catalyst 4500 Series Switches
rep segment
• REP ports follow these rules:
– There is no limit to the number of REP ports on a switch; however, only two ports on a switch
can belong to the same REP segment.
– If only one port on a switch is configured in a segment, the port should be an edge port.
– If two ports on a swit ch belo ng to the same segme nt, they m ust be bot h edge ports, both regular
segment ports, or one regular port and on e edge no-neighbor port . An edge port and regular
segment port on a switch cannot belong to the same segment.
– If two ports on a switch belong to the same segment and o ne is configured as an edge port and
one as a regular segment port (a misconfiguration), the edge port is treated as a regular segment
port.
If you configure two ports i n a segment as t he primar y edge port , for example ports on diffe rent switche s,
the REP selects one of them to serve as the segment primary edge port. Enter the show rep topology
privileged EXEC command on a port in the segment to verify which port is the segment primary edge
port.
REP interfaces come up in a blocked state and remain in a blocked state until notified that it is safe to
unblock. You need to be aware of this to avoid sudden connec tion losses.
You should configure REP only in networks with red undancy. Configuring REP i n a network without
redundancy causes loss of connect ivity.
In networks where ports on a neighborin g switch do not support R EP, you can configure the non-REP
facing ports as edge no-neighbo r ports. These ports inheri t all properties of edge ports and you can
configure them as any other edge port, including to send STP or REP topology change notices to the
aggregation switch. In this case, the STP topology change notice (TCN) that is sent is a multiple
spanning-tree (MST) STP m essage.
Examples This example shows how to enable REP on a regular (nonedge) segment port:
Switch (config)# interface gigabitethernet1/0/1
Switch (config-if)# rep segment 100
This example shows how to enable REP on a port and identify the port as the REP primary edge port:
Switch (config)# interface gigabitethernet1/1
Switch (config-if)# rep segment 100 edge primary
This example shows how to configure the same configuration when the interface has no external REP
neighbor:
Switch# configure terminal
Switch (config)# interface gigabitethernet1/1
Switch (config-if)# rep segment 100 edge no-neighbor primary
This example shows how to enable REP on a port and identify the por t as the REP secondary edge port:
Switch (config)# interface GigabitEthernet1/1
Switch (config-if)# rep segment 100 edge
You can verify your settings by entering the show interfaces rep privileged EXEC command. To verify
which port in the segment is the primary edge port, enter the show rep topology privileged EXEC
command .